/* Exercise 4.5 - other mathematical functions
* I could add more functions, but you get the idea */
void parseCommand(char s[])
{
double t;
/* Commands for ex 4.4 - stack commands */
if (0 == strcmp(s,"view"))
printtop(); /* view top element on stack */
else if (0 == strcmp(s, "duplicate"))
duplicate(); /* duplicate top element on stack */
else if (0 == strcmp(s, "swap"))
swap(); /* swap top two elements on stack */
else if (0 == strcmp(s, "clear"))
clear(); /* clear stack */
/* Commands for 4.5 - maths functions */
else if (0 == strcmp(s,"sin"))
push(sin(pop()));
else if (0 == strcmp(s,"exp"))
push(exp(pop()));
else if (0 == strcmp(s,"pow")) {
t = pop();
push(pow(pop(),t));
}
/* misc functions */
else if (0 == strcmp(s, "stack"))
viewstack();
else if (0 == strcmp(s, "vars"))
viewvars();
else
printf("error: not a valid command\n");
}
/* reverse Polish calculator */
main()
{
int type;
double op2;
char s[MAXOP];
while ((type = getop(s)) != EOF)
{
switch (type)
{
case NUMBER:
push(atof(s));
break;
case '"':
duptop();
break;
case '\'':
printtop();
break;
case '!':
swaptop2();
break;
case '+':
push(pop() + pop());
break;
case '*':
push(pop() * pop());
break;
case '-':
op2 = pop();
push(pop() - op2);
break;
case '/':
op2 = pop();
if (op2 != 0.0)
{
push(pop() / op2);
}
else
{
printf("error: zero divisor\n");
}
break;
case '%':
op2 = pop();
if (op2 != 0.0)
{
push(((int) pop()) % (int) op2);
}
else
{
printf("error: zero divisor\n");
}
break;
case '^':
op2 = pop();
push(pow(pop(), op2));
break;
case '#':
push(exp(pop()));
break;
case '$':
push(sin(pop()));
break;
case '\n':
printf("\t%.8g\n", pop());
break;
default:
printf("error: unknown command %s\n", s);
break;
}
}
return 0;
}
/*perform a process switch*/
void handletimerinterrupt(short segment, short sp)
{
int i,cntr=79;
/*save current process*/
process_table[current_process].segment=segment;
process_table[current_process].sp=sp;
/*print out the active processes at the top of the screen*/
for (i=MAXPROCESSES-1; i>=0; i--)
{
if (process_table[i].active>0)
{
printtop('P',cntr-5);
printtop((char)(i+0x30),cntr-4);
printtop(' ',cntr-3);
if (process_table[i].active==1)
printtop('A',cntr-2);
else if (process_table[i].active==2)
printtop('W',cntr-2);
else if (process_table[i].active==3)
printtop('K',cntr-2);
printtop(' ',cntr-1);
printtop(' ',cntr);
cntr=cntr-6;
}
}
printtop(' ',cntr);
printtop(' ',cntr-1);
printtop(':',cntr-2);
printtop('s',cntr-3);
printtop('e',cntr-4);
printtop('s',cntr-5);
printtop('s',cntr-6);
printtop('e',cntr-7);
printtop('c',cntr-8);
printtop('o',cntr-9);
printtop('r',cntr-10);
printtop('P',cntr-11);
/*find an active process round robin style*/
i=current_process;
do
{
i++;
if (i==MAXPROCESSES)
i=0;
} while(process_table[i].active!=1);
current_process=i;
/*restore that process*/
timer_restore(process_table[current_process].segment,process_table[current_process].sp);
}
/* reverse Polish calculator */
int main()
{
int type;
double op2;
char s[MAXOP];
char varDetected = FALSE;
while ((type = getop(s)) != EOF) {
switch (type) {
case NUMBER:
if(varDetected == TRUE)
{
pushVarValue(atof(s));
varDetected = FALSE;
printf("%c -> %g", varsNames[varPos-1], varsValues[varPos-1]);
}
else
push(atof(s));
break;
case '+':
push(pop() + pop());
break;
case '*':
push(pop() * pop());
break;
case '-':
op2 = pop();
push(pop() - op2);
break;
case '/':
op2 = pop();
if (op2 != 0.0)
push(pop() / op2);
else
printf("error: zero divisor\n");
break;
case '%':
op2 = pop();
if (op2 != 0.0)
push((int) pop() % (int) op2);
else
printf("error: zero divisor (modulus)\n");
break;
case '=': // assign variable
varDetected = TRUE;
break;
case 'S': // Compute sine
push(sin(pop()));
break;
case 'E': // Compute exponential function
push(exp(pop()));
break;
case '^': // Raise to power
op2 = pop();
push(pow(pop(), op2));
break;
case 'P': // print top element from the stack
printf("Top element is: %g\n", printtop());
break;
case 'D': // duplicate top element from the stack
duplicate();
break;
case '>': // swap top elements from the stack
swap();
break;
case 'C': //clear entire stack
clear();
break;
case '\n':
//printf("\t%.8g\n", pop());
break;
default:
if(type >= 'a' && type <= 'z')
pushVarName(type);
else
printf("error: unknown command %s\n", s); break;
}
}
return 0;
}
/* reverse Polish calculator */
main()
{
int type;
double op2, last, vars[26];
char s[MAXOP], varname;
while ((type = getop(s)) != EOF)
{
switch (type)
{
case NUMBER:
push(atof(s));
break;
case '"':
duptop();
break;
case '\'':
printtop();
break;
case '!':
swaptop2();
break;
case '+':
push(pop() + pop());
break;
case '*':
push(pop() * pop());
break;
case '-':
op2 = pop();
push(pop() - op2);
break;
case '/':
op2 = pop();
if (op2 != 0.0)
{
push(pop() / op2);
}
else
{
printf("error: zero divisor\n");
}
break;
case '%':
op2 = pop();
if (op2 != 0.0)
{
push(((int) pop()) % (int) op2);
}
else
{
printf("error: zero divisor\n");
}
break;
case '^':
op2 = pop();
push(pow(pop(), op2));
break;
case '#':
push(exp(pop()));
break;
case '$':
push(sin(pop()));
break;
case ASSIGNVAR:
varname = s[0];
duptop();
vars[varname - 'a'] = pop();
break;
case 'a': case 'b': case 'c': case 'd': case 'e': case 'f': case 'g':
case 'h': case 'i': case 'j': case 'k': case 'l': case 'm': case 'n':
case 'o': case 'p': case 'q': case 'r': case 's': case 't': case 'u':
case 'v': case 'w': case 'x': case 'y': case 'z':
push(vars[type - 'a']);
break;
case '?':
push(last);
break;
case '\n':
last = pop();
printf("\t%.8g\n", last);
break;
default:
printf("error: unknown command %s\n", s);
break;
}
}
return 0;
}
int main(void)
{
/* reverse Polish calculator */
int type;
double op2;
char s[MAXOP];
while ((type = getop(s)) != EOF) {
switch (type) {
case NUMBER:
push(atof(s) * sign);
sign = 1; /* reset sign */
break;
case SIN:
push(sin(pop()));
break;
case COS:
push(cos(pop()));
break;
case EXP:
push(exp(pop()));
break;
case POW:
op2 = pop();
push(pow(pop(), op2));
break;
case SQRT:
push(sqrt(pop()));
break;
case '+':
push(pop() + pop());
break;
case '*':
push(pop() * pop());
break;
case '-':
op2 = pop();
push(pop() - op2);
break;
case '/':
op2 = pop();
if (op2 != 0.0)
push(pop() / op2);
else
printf("error: zero devision\n");
break;
case '%':
op2 = pop();
if (op2 != 0)
push(fmod(pop(), op2));
else
printf("error: zero devision\n");
break;
case '\n':
if (popallowed)
printf("\t%.8g\n", pop());
else
popallowed = 1;
break;
case '?':
printtop();
break;
case '&':
dupetop();
break;
case '~':
swaptop();
break;
case '!':
clrstack();
break;
default:
printf("error: unknown command\n");
break;
}
}
return 0;
}
