Inital commitHEADmaster

31 files changed, 908 insertions, 0 deletions

diff --git a/accel.c b/accel.c
new file mode 100644
index 0000000..6b61c69
--- /dev/null
+++ b/accel.c
@@ -0,0 +1,14 @@
+/* Find the acceleration */
+
+#include <stdio.h>
+
+int main()
+{
+    static float FORCE_OF_GRAVITY = 9.81;
+    int pullforce = 20;
+    float coeffOfFriction = 0.2;
+    float weight = 5.0;
+    /*calculate and display acceleration */
+    printf("Acceleration a = %f(m/s^2)\n",(pullforce-coeffOfFriction*weight*FORCE_OF_GRAVITY)/weight);
+    return 0;
+}
diff --git a/accel_def-macro.c b/accel_def-macro.c
new file mode 100644
index 0000000..83b08cc
--- /dev/null
+++ b/accel_def-macro.c
@@ -0,0 +1,16 @@
+#include <stdio.h>
+
+#define M_G 9.81
+
+int main()
+{
+    /*Variables*/
+    double mu = 0.2;
+    double m = 5.0;
+    double p = 20.0;
+    
+    double a = (p-mu*m*M_G)/m;
+    
+    printf("Acceleration a=%f(m/s^2)\n",a);
+    return 0;
+    }
diff --git a/accel_var.c b/accel_var.c
new file mode 100644
index 0000000..522267f
--- /dev/null
+++ b/accel_var.c
@@ -0,0 +1,19 @@
+/* Calculate the acceleation using variables */
+
+#include <stdio.h>
+
+int main()
+{
+    /*declare variables*/
+    double mu = 0.2; //friction coefficient
+    double m = 5.0;  //mass
+    double p = 20.0; //external force
+    
+    /*calculate accelearation*/
+    double a = (p-mu*m*9.81)/m;
+    
+    //Display output
+    
+    printf("Acceleration a = %f (m/s^2)\n", a);
+    return 0;
+}
diff --git a/accelarray.c b/accelarray.c
new file mode 100644
index 0000000..293b841
--- /dev/null
+++ b/accelarray.c
@@ -0,0 +1,36 @@
+/*  File: accelarray.c
+    Calculate the acceleration using arrays fora ccel and time using 11 points */
+
+#include <stdio.h>
+#include <math.h>
+
+#define M_G 9.81
+#define N 11
+
+int main()
+{
+    double a[N],t[N];
+    double mu=0.2;
+    double m = 5.0;
+    double p;
+    int i;
+    
+    double t0 = 0.0;
+    double tf = 10.0;
+    
+    for(i=0;i<N;i++)
+    {
+        t[i] = t0 + i*(tf-t0)/(N-1);
+        p = 4*sin(t[i]-3)+20;
+        a[i] = (p-mu*m*M_G)/m;
+    }
+    
+    printf("time(s) accel (m/s^2)\n");
+    printf("--------------------\n");
+    for(i=0;i<N;i++)
+    {
+        printf("%8.4f%5c%8.4f\n",t[i],'\0',a[i]);
+    }
+    return 0;
+    
+}
diff --git a/accelmultiplefunctions.c b/accelmultiplefunctions.c
new file mode 100644
index 0000000..2db46b8
--- /dev/null
+++ b/accelmultiplefunctions.c
@@ -0,0 +1,36 @@
+/*  File: accelmultiplefunctions.c
+    Calculate acceleration
+    both force and acceleration are calculated using functions */
+    
+#include <stdio.h>
+#define M_G 9.81
+
+//Calculate the force
+
+double force(double t)
+{
+    double p;
+    p = 4*(t-3)+20;
+    printf("Froce p=%f(N)\n",p);
+    return p;
+}
+
+double accel(double t, double mu, double m)
+{
+    double a,p;
+    
+    p = force(t);
+    a = (p-mu*m*M_G)/m;
+    return a;
+}
+
+int main()
+{
+    double a, mu, m, t;
+    
+    mu = 0.2;
+    m = 5;
+    t = 2;
+    printf("Acceleration a = %f (m/s^2)\n",accel(t,mu,m));
+    return 0;
+}
diff --git a/addition.c b/addition.c
new file mode 100644
index 0000000..fa21bac
--- /dev/null
+++ b/addition.c
@@ -0,0 +1,16 @@
+/*File: addition.c
+Doing stuff with functions */
+
+#include <stdio.h>
+
+int addition(int a, int b)
+{
+    return a + b;
+}
+
+int main()
+{
+    int sum = addition(5,6);
+    printf("Sum is %i\n",sum);
+    return 0;
+}
diff --git a/celciustofarenhight.c b/celciustofarenhight.c
new file mode 100644
index 0000000..bde6de6
--- /dev/null
+++ b/celciustofarenhight.c
@@ -0,0 +1,12 @@
+/* CelsiusToFahreneit */
+#include <stdio.h> 
+#include<stdlib.h> 
+int main() 
+{
+    double input;
+    printf("Give me a number: ");
+    scanf("%lf", &input);
+    double answer = (input * (9.0 / 5.0) + 32);
+    printf("%8.4lf C = %8.4lf F\n\n", input,answer);
+    return 0;
+}
diff --git a/cpp/functions.c b/cpp/functions.c
new file mode 100644
index 0000000..1cb8d01
--- /dev/null
+++ b/cpp/functions.c
@@ -0,0 +1,3 @@
+#include <stdio.h>
+int main ()
+{}
diff --git a/cpp/stuff1.c b/cpp/stuff1.c
new file mode 100644
index 0000000..8f0269c
--- /dev/null
+++ b/cpp/stuff1.c
@@ -0,0 +1,162 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#define A 4
+#define B 2
+
+int main()
+{
+    char doagain = 'Y';
+    while (doagain=='Y'|| doagain == 'y')
+    {
+        float a[A];
+        
+        float w;
+        float x;
+        float y;
+        float z;
+        
+        float fw;
+        float fx;
+        float fy;
+        float fz;
+
+        float b[2][B];
+        
+        float m;
+        float n;
+        float o;
+        float p;
+
+        float im;
+        float in;
+        float io;
+        float ip;
+             
+        int any;
+        printf("press 1 to convert F to C, \n press 2 to convert Inchs to Centimeters, \nor press 3 to convert Degrees to Radians.");
+        scanf("%i",&any);
+        
+        if (any < 1 || any > 3)
+        {
+                printf("error! try again! \n");
+        }
+        
+        if (any == 1)
+        {
+        /*Changes a given number of celsius to farenhight*/
+            printf("Enter first celsius value");
+            scanf("%f",&w);
+
+            printf("Enter second celsius value");
+            scanf("%f",&x);
+
+            printf("Enter third celsius value");
+            scanf("%f",&y);
+
+            printf("Enter fourth celsius value");
+            scanf("%f",&z);
+
+            fw = ((9.0 / 5.0)*(w + 32));
+            fx = ((9.0 / 5.0)*(x + 32));
+            fy = ((9.0 / 5.0)*(y + 32));
+            fz = ((9.0 / 5.0)*(z + 32));
+
+            a[0]=fw;
+            a[1]=fx;
+            a[2]=fy;
+            a[3]=fz;
+
+            printf("\n\n Celsius to Fahrenheit Array \n a[0]= %.2f, a[1]= %.2f, a[2]%.2f,a[3] %.2f\n\n",a[0],a[1],a[2],a[3]);
+        }
+        
+        if (any == 2)
+        {
+            /*This (probably) turns an entered number of centimeters to inches*/
+
+            printf("Enter first value for centimeters");
+            scanf("%f",&m);
+
+            printf("Enter second value for centimeters");
+            scanf("%f",&n);
+
+            printf("Enter third value for centimeters");
+            scanf("%f",&o);
+
+            printf("Enter fourth value for centimeters");
+            scanf("%f",&p);
+
+            im = m*2.54;
+            in = n*2.54;
+            io = o*2.54;
+            ip = p*2.54;
+
+            b[0][0]=im;
+            b[0][1]=in;
+            b[1][0]=io;
+            b[1][1]=ip;
+
+            printf("\n Cm to Inches Array \nb[0][0]=%.2f,b[0][1]=%.2f\n,b[1][0]=%.2f,b[1][1]=%.2f\n\n",b[0][0],b[0][1],b[1][0],b[1][1]);
+        }
+        
+        if (any == 3)
+        {
+            /*Radiant*/
+            float h;
+            float i;
+            float j;
+            float k;
+            
+            printf("Enter the first value in degrees");
+            scanf("%f",&h);
+            
+            printf("Enter the second value in degrees");
+            scanf("%f",&i);
+            
+            printf("Enter the thind value in degrees");
+            scanf("%f",&j);
+            
+            printf("Enter the fourth value in degrees");
+            scanf("%f",&k);
+            float degree[4];
+                    
+            degree[0] = h;
+            degree[1] = i;
+            degree[2] = j;
+            degree[3] = k;
+                    
+            float rad[4];
+            
+            rad[0] = h*(0.0175);
+            rad[1] = i*(0.0175);
+            rad[2] = j*(0.0175);
+            rad[3] = k*(0.0175);
+            
+            float matrix[6][4];
+            int index = 0;
+            while (index < 4)
+            {
+                matrix[0][index] = sin(rad[index]); 
+                matrix[1][index] = cos(rad[index]);     
+                matrix[2][index] = tan(rad[index]);
+                matrix[3][index] = asin(matrix[0][index]); 
+                matrix[4][index] = acos(matrix[1][index]);     
+                matrix[5][index] = atan(matrix[2][index]);
+                index = index+1;
+            }
+        //Matrix has functions stored in columns
+            int row = 0;
+            int col = 0;
+        ////////   6      6    3   3   3   4    4    4
+            printf("\ndegree radian sin  cos  tan  asin  acos  atan\n");
+            while(col < 4)
+            {
+                printf("%.4f %.4f %.2f %.2f %.2f %.3f %.3f %.3f\n",degree[col],rad[col],matrix[0][col],matrix[1][col],matrix[2][col],matrix[3][col],matrix[4][col],matrix[5][col]);
+                col++;
+            }
+        }   
+    printf("type Y to doagain or N to quit");
+    scanf(" %c",&doagain);
+    }
+    return 0;
+}
diff --git a/cpp/whilelooppractice.c b/cpp/whilelooppractice.c
new file mode 100644
index 0000000..f1d1c9b
--- /dev/null
+++ b/cpp/whilelooppractice.c
@@ -0,0 +1,13 @@
+#include <stdio.h>
+int main()
+{printf("Hello World!\n");
+int ear=40;
+while (ear>20)
+{
+    printf("Elephants are pretty cool!\n");
+    printf("%i",ear);
+    ear=ear-1;
+}
+return 0;
+}
+
diff --git a/first_code.c b/first_code.c
new file mode 100644
index 0000000..87be6e7
--- /dev/null
+++ b/first_code.c
@@ -0,0 +1,8 @@
+/* this is the first code!*/
+#include <stdio.h>
+
+int main()
+{
+    printf("I love college\n");
+    return 1;
+}
diff --git a/force.c b/force.c
new file mode 100644
index 0000000..70d371b
--- /dev/null
+++ b/force.c
@@ -0,0 +1,26 @@
+/*File force.c
+Calculate the piecewise time force. The formula depends on wether time t is less or equal to 3 seconds */
+#include <stdio.h>
+#define M 3
+
+int main()
+{
+    int x = 0;
+    while(x<10)
+    {
+        double p,t;
+        printf("Useing time %i", x);
+        t= x;
+        if(t<=M)
+        {
+            p = 20;
+        }
+        else
+        {
+            p = 4*(t+2);
+        }
+        printf("Force p = %f (N)\n",p);
+        x++;
+    }
+    return 0;
+}
diff --git a/force2.c b/force2.c
new file mode 100644
index 0000000..8806617
--- /dev/null
+++ b/force2.c
@@ -0,0 +1,25 @@
+/*File : force2.c Calculate the peicewise time force. The formulas depend on wether time t is 0<=t<=3 or t>0*/
+#include <stdio.h>
+#define M 3
+
+int main()
+{
+
+    double p, t;
+    printf("Please input time in seconds: ");
+    scanf("%lf",&t);
+    if(0<=t && t<=M){
+        p = 20;
+        printf("Force p = %f (N)\n",p);
+    }
+    else if(t>3)
+    {
+        p = 4*(t+2);
+        printf("Force p = %f (N)\n",p);
+    }
+    else
+    {
+        printf("Invalid input, time is never negitive\n");
+    }
+    return 0;
+}
diff --git a/forsin.c b/forsin.c
new file mode 100644
index 0000000..23e7250
--- /dev/null
+++ b/forsin.c
@@ -0,0 +1,18 @@
+/* File: forsin.c
+   calculate the function sinc(x) = sin(x)/x
+   for x from -10 to 10 with step size 5 */
+ 
+#include <stdio.h>
+#include <math.h>
+   
+int main()
+{
+    int x;
+    printf("%3c | %5s\n",'x',"sinc(x)");
+    printf("-------------\n");
+    for(x=-10;x<=10;x+=5)
+    {
+        printf("%3i | %6.3f\n",x,sin(x));
+    }
+    return 0;
+}
diff --git a/gpa.c b/gpa.c
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/gpa.c
diff --git a/ifgrade.c b/ifgrade.c
new file mode 100644
index 0000000..61dbd10
--- /dev/null
+++ b/ifgrade.c
@@ -0,0 +1,46 @@
+/*File: ifgrade.c
+Reads greades A, B, C, D ,F from the screen and prints the corresponding numerical value (4, 3, 2, 1, 0) of the score*/
+
+#include <stdio.h>
+
+int main()
+{
+    char grade;
+    double score;
+    printf("Enter a grade [A,B,C,D,F]: ");
+    scanf(" %c",&grade);
+    /*Make the character entered upper case if it is lower case*/
+    if(grade >= 97)
+    {
+        grade = grade-32;
+    }
+    if(grade=='A')
+    {
+        score = 4.0;
+    }
+    else if(grade=='B')
+    {
+        score = 3.0;
+    }
+    else if(grade=='C')
+    {
+        score = 2.0;
+    }
+    else if(grade=='D')
+    {
+        score = 1.0;
+    }
+    else if(grade=='F')
+    {
+        score = 0.0;
+    }
+    else
+    {
+        score = -1;
+        printf("Invalid grade %c\n",grade);
+    }
+    
+    if(score != -1)
+    printf("The score for the grade %c is %.2f\n",grade,score);
+    return 0;
+}
diff --git a/linear_spaced.c b/linear_spaced.c
new file mode 100644
index 0000000..d8dd301
--- /dev/null
+++ b/linear_spaced.c
@@ -0,0 +1,33 @@
+/*  File: linear_spaced.c
+    Generates linearly spaced atat for an array with N elements from x0 to xf*/
+    
+#include <stdio.h>
+
+#define N 11
+
+int main()
+{
+    double  x[N],
+            x0 = 0.0,
+            xf = 5.0;
+    double  j = x0;
+    
+    int i;
+    
+    printf("%-4c",'c');
+    /*  generate linearly spaced data for an array with N elements */
+    double step = (xf - x0)/((double)N);
+    for(i=0;i<N;i++)
+    {
+        printf(" %4d ",i);
+        x[i] = j;
+        j += step;
+    }
+    printf("\n%-4c",'c');
+    for(i=0;i<N;i++)
+    {
+        printf(" %4.2f ",x[i]);
+    }
+    printf("\n");
+    return 0;
+}
diff --git a/matmult.c b/matmult.c
new file mode 100644
index 0000000..d1b2f2c
--- /dev/null
+++ b/matmult.c
@@ -0,0 +1,80 @@
+/*  File: matmult.c
+    Multiplication of two matricies*/
+#include <stdio.h>
+
+#define M 10
+#define N 20
+#define P 30
+
+int main()
+{
+    double a[M][N];
+    double b[N][P];
+    double c[M][P];
+    int i;
+    int j;
+    int k;
+
+    int pop1,pop2;
+    for(pop1=0;pop1<M;pop1++)
+    {
+        for(pop2=0;pop2<N;pop2++)
+        {
+            a[pop1][pop2] = pop1+pop2;
+        }   
+    }
+    
+    for(pop1=0;pop1<M;pop1++)
+    {
+        for(pop2=0;pop2<P;pop2++)
+        {
+            b[pop1][pop2] = pop1*pop2;
+        }
+    }
+
+    for(i=0;i<M;i++)
+    {
+        for(j=0;j<P;j++)
+        {
+            c[i][j] = 0;
+            for(k=0;k<N;k++)
+            {
+                c[i][j] += a[i][k]*b[k][j];
+            }
+        }
+    }
+    
+    printf("Matrix a is\n");
+    int l,m;
+    
+    for(l = 0;l<M;l++)
+    {
+        for(m = 0; m<N;m++)
+        {
+            printf("%3i ",(int)a[l][m]);
+        }
+        printf("\n");
+    }
+    
+    printf("\nMatrix b is\n");
+    for(l = 0;l<M;l++)
+    {
+        for(m = 0; m<N;m++)
+        {
+            printf("%3i ",(int)b[l][m]);
+        }
+        printf("\n");
+    }
+    
+    printf("\nMatrix c is\n");
+    for(l = 0;l<M;l++)
+    {
+        for(m = 0; m<N;m++)
+        {
+            printf("%5i ",(int)c[l][m]);
+        }
+        printf("\n");
+    }
+    
+    return 0;
+}
diff --git a/matrixv.c b/matrixv.c
new file mode 100644
index 0000000..0b1ea3a
--- /dev/null
+++ b/matrixv.c
@@ -0,0 +1,30 @@
+/*  File: matrixv.c
+    Calculate matrix equation b = Ax */
+    
+#include <stdio.h>
+
+#define M 3
+#define N 3
+
+int main()
+{
+    double a[M][N] = {{ 3,5,6},
+                      { 4,2,1},
+                      { 0,7,1}};
+    double v[N] = {2,1,-2};
+    double b[M];
+    
+    int i,j;
+    
+    for(i = 0;i<N;i++)
+    {
+        b[i] = 0;
+        for(j=0;j<N;j++)
+        {
+            b[i] += a[i][j] * v[j];
+        }
+    }
+    printf("b=%g,%g,%g\n",b[0],b[1],b[2]);
+    return 0;
+    
+}
diff --git a/mean.c b/mean.c
new file mode 100644
index 0000000..34ec21c
--- /dev/null
+++ b/mean.c
@@ -0,0 +1,26 @@
+/*  File: mean.c
+    Calculate the mean value for the elements in an array */
+    
+#include <stdio.h>
+
+#define N 8
+
+int main()
+{
+    /*Declare array a with initialization */
+    double a[N] = {3.0,21.0,0.0,-3.0,34.0,-14.0,45.0,18.0};
+    double  sum,
+            meanval;
+            
+    int i;
+    
+    sum = 0;
+    
+    for(i=0;i<N;i++)
+    {
+        sum += a[i];
+    }
+    meanval = sum/(double)N;
+    printf("The mean value of the array is %f\n",meanval);
+    return 0;
+}
diff --git a/mile2km.c b/mile2km.c
new file mode 100644
index 0000000..f1c9e66
--- /dev/null
+++ b/mile2km.c
@@ -0,0 +1,12 @@
+
+#include <stdio.h>
+
+int main()
+{
+    float miles = 23.5;
+    float conversion = 1.6093;
+    float answer = miles * conversion;
+    
+    printf("%f miles is = %f Km\n",miles,answer);
+    }
+    
diff --git a/nestedloop.c b/nestedloop.c
new file mode 100644
index 0000000..d249dca
--- /dev/null
+++ b/nestedloop.c
@@ -0,0 +1,23 @@
+/*File: nestedloop.c
+    Make a multiplication table useing 2 nested loops
+    */
+
+#include <stdio.h>
+
+int main()
+{
+    int x, y;
+    printf("xxx %-3i %-3i %-3i %-3i %-3i %-3i %-3i %-3i %-3i %-3i\n",1,2,3,4,5,6,7,8,9,10);
+    printf("------------------------------------------\n");
+    for(x=1;x<=10;x++)
+    {
+        printf("%-3i|",x);
+        for(y=1;y<=x;y++)
+        {
+            printf("%-3i ",x*y);
+        }
+        printf("\n");
+    }
+    printf("------------------------------------------\n");
+    return 0;
+}
diff --git a/numbers.c b/numbers.c
new file mode 100644
index 0000000..b402d59
--- /dev/null
+++ b/numbers.c
@@ -0,0 +1,31 @@
+#include <stdio.h>
+
+int main()
+{
+        float numbers [16] ={   (2*3), /*a*/
+                                (1/5), /*b*/
+                                (1/2), /*c*/
+                                (3/2), /*d*/
+                                (1/3), /*e*/
+                                (2/3), /*f*/
+                                (1.0/5),/*g*/
+                                (1.0/2),/*h*/
+                                (3.0/2),/*i*/
+                                (1.0/3),/*j*/
+                                (2.3/3),/*k*/
+                                (1/5.0),/*l*/
+                                (1/2.0),/*m*/
+                                (3/2.0),/*n*/
+                                (1/3.0),/*o*/
+                                (2/3.0),/*p*/
+                            };
+        int x = 0;
+        while(x<16)
+        {
+                char letter = x+97;
+                //printf("%c is %f and %.20f\n",letter,numbers[x],numbers[x]);
+                x++;
+        }
+        return 0;
+}
+
diff --git a/pointer.c b/pointer.c
new file mode 100644
index 0000000..48c93ca
--- /dev/null
+++ b/pointer.c
@@ -0,0 +1,16 @@
+/* Use a pointer to assign the adderss of a variable */
+
+#include <stdio.h>
+
+int main() 
+{
+    int i, *p;
+    i=10;
+    p=&i;
+    printf("The value of i is %d\n",i);
+    printf("The address of i is %p\n", &i);
+    char c = 'a';
+    printf("Char: %c\n",c);
+    return 0;
+    
+}
diff --git a/prints.c b/prints.c
new file mode 100644
index 0000000..cd088af
--- /dev/null
+++ b/prints.c
@@ -0,0 +1,8 @@
+#include <stdio.h>
+
+int main()
+{
+//        printf("?/?=\n");
+        printf("??=\n");
+        return 0;
+}
diff --git a/problem1.c b/problem1.c
new file mode 100644
index 0000000..1f85ff0
--- /dev/null
+++ b/problem1.c
@@ -0,0 +1,14 @@
+/* Find the acceleration */
+
+#include <stdio.h>
+
+int main()
+{
+    static float FORCE_OF_GRAVITY = 9.81;
+    int pullforce = 10;
+    float coeffOfFriction = 0.3;
+    float weight = 6.0;
+    /*calculate and display acceleration */
+    printf("Acceleration a = %f(m/s^2)\n",(pullforce-coeffOfFriction*weight*FORCE_OF_GRAVITY)/weight);
+    return 0;
+}
diff --git a/sinr_r.c b/sinr_r.c
new file mode 100644
index 0000000..9128dda
--- /dev/null
+++ b/sinr_r.c
@@ -0,0 +1,55 @@
+/*  File sinr_r.c
+    Calculate function sinr(x,y) = sin(sqrt(x*x+y*y))/sqrt(x*x+y*y)
+    for x from -10 to 10 with step size 10,
+    and for y from -10 to 10 with step size 10 */
+
+#include <stdio.h>
+#include <math.h>
+#include <float.h>
+
+int main()
+{
+    double  x,x0,xf,xstep,
+            y,y0,yf,ystep,
+            function, r,
+            xsq,ysq,sum;
+    int i,j,nx,ny;
+    
+    printf("%10c %10c %10s %10s %10s %10s\n",'x','y',"xsqared","ysquared","x^2+y^2","sinr(x,y)");
+    printf("--------------------------------\n");
+    /*Initial, final, step size, number of points*/
+    x0 = -10.0;
+    xf = 10.0;
+    xstep = 10.0;
+    nx = (xf-x0)/xstep + 1;
+    y0=-10.0;
+    yf=10.0;
+    ystep=10.0;
+    ny = (yf-y0)/ystep + 1;
+    
+    for(i=x0;i<=xf;i+=xstep)
+    {
+        x = i;
+        for(j=y0;j<=yf;j+=ystep)
+        {
+            y = j;
+            xsq = x*x;
+            ysq = y*y;
+            sum = xsq + ysq;
+            printf("%10.4f %10.4f %10.4f %10.4f %10.4f ",x,y,xsq,ysq,sum);
+            
+            /*If the sum has a value smaller than elipson, sinr(x,y) = 1 */
+            if(fabs(sum) < FLT_EPSILON)
+            {
+                function = 1;
+            }
+            else
+            {
+                function = sin(sum)/sum;
+            }
+            printf("%10.4f\n",function);
+        }
+    }
+
+    return 0;
+}
diff --git a/sintest.c b/sintest.c
new file mode 100644
index 0000000..aa9d4b0
--- /dev/null
+++ b/sintest.c
@@ -0,0 +1,9 @@
+#include <math.h>
+#include <stdio.h>
+
+int main()
+{
+    printf("Sine of 90 degrees is %f",sin(90));
+    return 0;
+    
+}
diff --git a/sphererevol.c b/sphererevol.c
new file mode 100644
index 0000000..ff1bbf8
--- /dev/null
+++ b/sphererevol.c
@@ -0,0 +1,14 @@
+/*Calculates the volume of a sphere*/
+#include <math.h>
+#include <stdio.h>
+
+int main()
+{
+    double radius = 5;
+    float pi = M_PI;
+    double radiusCubed = pow(radius,3);
+    float answer = (4*pi*radiusCubed/3);
+    
+    printf("The volume of a sphere with radius %f is %f\n",radius,answer);
+    return 0;
+    }
diff --git a/switchgrade.c b/switchgrade.c
new file mode 100644
index 0000000..b22cd66
--- /dev/null
+++ b/switchgrade.c
@@ -0,0 +1,42 @@
+/*File: switchgrade.c 
+This program reads a grade from the screen and prints the corresponding numerical value of the score.*/
+
+#include <stdio.h>
+
+int main()
+{
+    char grade;
+    double score;
+    
+    printf("Enter a grade [A,B,C,D,F]: ");
+    scanf(" %c",&grade);
+    
+    //Force all characters to be uppercase
+    if(grade>=97)
+    {
+        grade = grade-32;
+    }
+    
+    switch(grade)
+    {
+        case 'A':
+            score += 1.0;
+        case 'B':
+            score += 1.0;
+        case 'C':
+            score += 1.0;
+        case 'D':
+            score += 1.0;
+        case 'F':
+            break;
+        default:
+            score = -1;
+            printf("Invalid grade %c\n",grade);
+            break;
+     }
+     if(score != -1)
+     {
+        printf("The score for the grade %c is %.2f\n",grade,score);
+     }
+     return 0;
+}
diff --git a/transpose.c b/transpose.c
new file mode 100644
index 0000000..32c769b
--- /dev/null
+++ b/transpose.c
@@ -0,0 +1,65 @@
+/*File: transpose.c The transpose of matrix A is obtained by interchanging the rows and columns. */
+#include <stdio.h>
+
+#define M 10
+#define N 20
+
+int main()
+{
+
+    double a[M][N], b[N][M];
+    int row,col;
+
+    for(row=0;row<M;row++)
+    {
+        for(col=0;col<N;col++)
+        {
+            a[row][col] = row*col;
+        }
+    }
+
+    for(row=0;row<M;row++)
+    {
+        for(col=0;col<N;col++)
+        {
+            b[col][row]=a[row][col];
+        }
+    }
+    
+    printf("Matrix a is\n");
+    for(row=0;row<M;row++)
+    {
+        for(col=0;col<N;col++)
+        {
+            printf("%3i ",(int)a[row][col]);
+        }
+        printf("\n");
+    }
+    
+    printf("\nMatrix b is \n");
+    for(row=0;row<N;row++)
+    {
+        for(col=0;col<M;col++)
+        {
+            printf("%3i ",(int)b[row][col]);
+        }
+        printf("\n");
+    }
+    
+    printf("\nAn identity matrix of size %i\n",M);
+    int ident[M][M];
+    for(row=0;row<M;row++)
+    {
+        ident[row][row] = 1;
+    }
+    
+    for(row=0;row<M;row++)
+    {
+        for(col=0;col<M;col++)
+        {
+            printf("%i ",ident[row][col]);
+        }
+        printf("\n");
+    }
+    return 0;
+}