Data commit

Task/Arithmetic-Complex/C/arithmetic-complex-1.c

@@ -0,0 +1,32 @@
+#include <complex.h>
+#include <stdio.h>
+
+void cprint(double complex c)
+{
+  printf("%f%+fI", creal(c), cimag(c));
+}
+void complex_operations() {
+  double complex a = 1.0 + 1.0I;
+  double complex b = 3.14159 + 1.2I;
+
+  double complex c;
+
+  printf("\na="); cprint(a);
+  printf("\nb="); cprint(b);
+
+  // addition
+  c = a + b;
+  printf("\na+b="); cprint(c);
+  // multiplication
+  c = a * b;
+  printf("\na*b="); cprint(c);
+  // inversion
+  c = 1.0 / a;
+  printf("\n1/c="); cprint(c);
+  // negation
+  c = -a;
+  printf("\n-a="); cprint(c);
+  // conjugate
+  c = conj(a);
+  printf("\nconj a="); cprint(c); printf("\n");
+}

Task/Arithmetic-Complex/C/arithmetic-complex-2.c

@@ -0,0 +1,61 @@
+typedef struct{
+        double real;
+        double imag;
+} Complex;
+
+Complex add(Complex a, Complex b){
+        Complex ans;
+        ans.real = a.real + b.real;
+        ans.imag = a.imag + b.imag;
+        return ans;
+}
+
+Complex mult(Complex a, Complex b){
+        Complex ans;
+        ans.real = a.real * b.real - a.imag * b.imag;
+        ans.imag = a.real * b.imag + a.imag * b.real;
+        return ans;
+}
+
+/* it's arguable that things could be better handled if either
+   a.real or a.imag is +/-inf, but that's much work */
+Complex inv(Complex a){
+        Complex ans;
+        double denom = a.real * a.real + a.imag * a.imag;
+        ans.real =  a.real / denom;
+        ans.imag = -a.imag / denom;
+        return ans;
+}
+
+Complex neg(Complex a){
+        Complex ans;
+        ans.real = -a.real;
+        ans.imag = -a.imag;
+        return ans;
+}
+
+Complex conj(Complex a){
+        Complex ans;
+        ans.real =  a.real;
+        ans.imag = -a.imag;
+        return ans;
+}
+
+void put(Complex c)
+{
+        printf("%lf%+lfI", c.real, c.imag);
+}
+
+void complex_ops(void)
+{
+  Complex a = { 1.0,     1.0 };
+  Complex b = { 3.14159, 1.2 };
+
+  printf("\na=");   put(a);
+  printf("\nb=");   put(b);
+  printf("\na+b="); put(add(a,b));
+  printf("\na*b="); put(mult(a,b));
+  printf("\n1/a="); put(inv(a));
+  printf("\n-a=");  put(neg(a));
+  printf("\nconj a=");  put(conj(a));  printf("\n");
+}