出现的问题是 + - * / 运行正确，但是sin cos pow 等运行结果出错，比如：3.14159265 2 / sin 的结果不是1，     2 3 pow 的结果不是8， 求大神，前辈指点，谢谢！

程序： calculator.c(主程序)+ popandpush.c + getop.c +getchandungetch.c + mathfnc.c
如下：
/*逆波兰计算器*/
#include <stdio.h>
#include <stdlib.h>
#include <math.h>

#define MAXOP 100
#define NUMBER '0'
#define NAME 'n'

int getop(char []);
void push(double);
double pop(void);
void mathfnc(char s[]);

main()
{
int type;
double op2;
char s[MAXOP];

while ((type = getop(s)) != EOF){
switch (type){
case NUMBER:
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 NAME:
mathfnc(s);
break;
case '\n':
printf("\t%.8g\n", pop());
break;
default:
printf("error:unknown command %s\n", s);
break;
}
}
return 0;
}
---------------------------------------
/*popandpush.c*/
#define MAXVAL 100
#include <stdio.h>

int sp = 0;
double val[MAXVAL];

void push(double f)
{
if (sp < MAXVAL)
val[sp++] = f;
else
printf("error:stack full, can't push %g\n", f);
}

double pop(void)
{
if(sp > 0)
return val[--sp];
else{
printf("error:stack empty\n");
return 0.0;
}
}
------------------------------
/*getop.c*/

#include <ctype.h>
#include <stdio.h>
#include <string.h>

#define NUMBER '0'
#define NAME 'n'

int getch(void);
void ungetch(int);

int getop(char s[])
{
int i, c;

while ((s[0] = c = getch()) == ' ' || c == '\t')
;
s[1] = '\0';
i = 0;
if (islower(c)){
while (islower(s[++i] = c = getch()))
;
s[i] = '\0';
if (c != EOF)
ungetch(c);
if (strlen(s) > 1)
return NAME;
else
return c;
}
if (!isdigit(c) && c != '.')
return c;
if (isdigit(c))
while (isdigit(s[++i] = c = getch()))
;
if(c == '.')   
while (isdigit(s[++i] = c = getch()))
;
s[i] = '\0';
if (c != EOF)
ungetch(c);
return NUMBER;
}
-------------------------------
/*getchandungetch.c*/
#define BUFSIZE 100
#include <stdio.h>

char buf[BUFSIZE];
int bufp = 0;

int getch(void)
{
return (bufp > 0) ? buf[--bufp] : getchar();
}

void ungetch(int c)
{
if (bufp >= BUFSIZE)
printf("ungetch:too many characers\n");
else
buf[bufp++] = c;
}
---------------------------
/*mathfnc.c*/
#include <stdio.h>
#include <string.h>
#include <math.h>

void mathfnc(char s[])
{
double op2;

if (strcmp(s, "sin") == 0)
push(sin(pop()));
else if (strcmp(s, "cos") == 0)
push(cos(pop()));
else if (strcmp(s, "exp") == 0)
push(exp(pop()));
else if (strcmp(s, "pow") == 0){
op2 = pop();
push(pow(op2, pop()));
}
else
printf("error: %s is not supported\n", s);   
}


[ 本帖最后由 lobsters 于 2013-3-15 16:51 编辑 ]

3.1415那个我试了是 1没错，至于那个 2 3 pow，想想是底数先出栈还是指数先出栈

可我的结果是0啊 我也看不出哪里错啊

把倒数第 5行改了先，至于你的结果是 0就不太懂了，我win7

人家楼主说了是ubuntu vim里编写的………你好歹找个小红帽运行下也行啊

这和用什么系统、编辑器写没什么关系。太长不看了，问题肯定是出在输入表达式的分析上，这是个细活儿很容易出纰漏，比如你考虑负数的输入了么。

一时兴起，也写了一个，交流一下程序结构设计的心得。

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<ctype.h>
#include<math.h>

typedef struct
{
    char * opstr;
    double (* opfun)(double *);
    int argc;
}OP_MAP;

double my_add(double * data);
double my_sub(double * data);
double my_mul(double * data);
double my_div(double * data);
double my_sin(double * data);
double my_cos(double * data);
double my_pow(double * data);

OP_MAP map[] = {
    {"+",    my_add, 2},
    {"-",    my_sub, 2},
    {"*",    my_mul, 2},
    {"/",    my_div, 2},
    {"sin",  my_sin, 1},
    {"cos",  my_cos, 1},
    {"pow",  my_pow, 2},
};

void cal(char * opstr, double * data, int * count);

int main()
{
    char str[1024], opstr[1024], *p, *pe;
    double data[1024] = {0}, val;
    int count;
   
    for(; gets(str) != NULL && *str != '\0'; printf("%f\n", data[count - 1]))
    for(count = 0, p = str;; p = pe)
    {
        while(isspace(*p)) p++;
        if(*p == '\0') break;
        val = strtod(p, &pe);
        if(p != pe)
        {
            data[count++] = val;
        }
        else
        {
            sscanf(p, "%s", opstr);
            pe = p + strlen(opstr);
            cal(opstr, data, &count);
        }
    }
   
    return 0;
}

void cal(char * opstr, double * data, int * count)
{
    int i, offset;
    for(i = 0; i < sizeof(map) / sizeof(OP_MAP); i++)
        if(strcmp(opstr, map[i].opstr) == 0)
        {
            offset = *count - map[i].argc;
            if(offset < 0) return;
            data[offset] = map[i].opfun(data + offset);
            *count = offset + 1;
        }
}

double my_add(double * data)
{
    return data[0] + data[1];
}

double my_sub(double * data)
{
    return data[0] - data[1];
}

double my_mul(double * data)
{
    return data[0] * data[1];
}

double my_div(double * data)
{
    return data[0] / data[1];
}

double my_sin(double * data)
{
    return sin(data[0]);
}

double my_cos(double * data)
{
    return cos(data[0]);
}

double my_pow(double * data)
{
    return pow(data[0], data[1]);
}

[ 本帖最后由 beyondyf 于 2013-3-16 01:55 编辑 ]