made commands maybe more readable, added ^

Signed-off-by: Daniel <steew0x8@protonmail.com>

3 files changed, 28 insertions, 7 deletions

diff --git a/cmds.c b/cmds.c
index 07707df..4884ec8 100644
--- a/cmds.c
+++ b/cmds.c
@@ -6,29 +6,43 @@
 #include <err.h>
 #include <string.h>
 
+#define LAST stack.val[stack.count-1]
+#define PREV stack.val[stack.count-2]
+#define REDUCE stack.val[--stack.count] = 0
+
 stack fceil(stack stack) {
-  stack.val[stack.count-1] = ceil(stack.val[stack.count-1]);
+  LAST = ceil(PREV);
   return stack;
 }
 
 stack ffloor(stack stack) {
-  stack.val[stack.count-1] = floor(stack.val[stack.count-1]);
+  LAST = floor(LAST);
   return stack;
 }
 
 stack flogB(stack stack) {
-  stack.val[stack.count-2] = log2(stack.val[stack.count-2])/log2(stack.val[stack.count-1]);
-  stack.val[--stack.count] = 0;
+  PREV = log2(PREV)/log2(LAST);
+  REDUCE;
   return stack;
 }
 
 stack fnegate(stack stack) {
-  stack.val[stack.count-1] *= -1;
+  LAST *= -1;
   return stack;
 }
 
 stack fpop(stack stack) {
-  stack.val[--stack.count] = 0;
+  REDUCE;
+  return stack;
+}
+
+stack fsqrt(stack stack) {
+  LAST = sqrt(LAST);
+  return stack;
+}
+
+stack finv(stack stack) {
+  LAST = 1/LAST;
   return stack;
 }
 
@@ -36,8 +50,10 @@ command CMD_LIST[] = {
   {"p", &fpop, "pop last element", 1},
   {"ceil", &fceil, "truncate to the next integer", 1},
   {"floor", &ffloor, "truncate to the previous integer", 1},
-  {"log", &flogB, "calculate logarithm in base LAST_NUM of LAST_NUM-1", 2},
+  {"log", &flogB, "calculate logarithm using last element as a base and the previous as the argument", 2},
   {"neg", &fnegate, "change last element's sign", 1},
+  {"sqrt", &fsqrt, "calculate the square root", 1},
+  {"inv", &finv, "invert last number", 1},
 };
 
 int compare(const void *s1, const void *s2) {
diff --git a/main.c b/main.c
index 4f9dd2e..b4c092f 100644
--- a/main.c
+++ b/main.c
@@ -68,6 +68,10 @@ int main() {
 	  s.stk.val[s.stk.count-2] = s.stk.val[s.stk.count-2]/s.stk.val[s.stk.count-1];
 	  s.stk.val[s.stk.count--] = 0; /* lower count by 1 */
 	  s.last_op = '/';
+	} else if (operator == '^') {
+	  s.stk.val[s.stk.count-2] = pow(s.stk.val[s.stk.count-2],s.stk.val[s.stk.count-1]);
+	  s.stk.val[s.stk.count--] = 0; /* lower count by 1 */
+	  s.last_op = '^';
 	} else;
       } else if (t == FUNCTION) {
 	/* check for special commands, else pass to exec() */
diff --git a/util.c b/util.c
index a6c831f..7d13e3b 100644
--- a/util.c
+++ b/util.c
@@ -7,6 +7,7 @@ const char OPERATOR_LIST[] = {
   '-',
   '*',
   '/',
+  '^',
   0
 };