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トップObjective-Cに関する質問lvalue C言語　関数エラー

編集履歴

質問編集履歴

2

文法の修正

2022/06/28 07:46

投稿

yusuke.
yusuke.

スコア66

test CHANGED
File without changes
test CHANGED
@@ -35,10 +35,17 @@
35
35
  #include <stdio.h>
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36
  #include <math.h>
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37
 
38
- float f(x);
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+ float f(float x){
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- float df(x);
40
- f(x) = x - cos(x);
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+ f(x) = x - cos(x);
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+ return f(x) ;
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+ }
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+
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+ float df(float x){
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- df(x) = 1.0 + sin(x);
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+ df(x) = 1.0 + sin(x);
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+ return df(x);
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+ }
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+
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+
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  int main(){
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  float f(x);
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  float df(x);
@@ -53,42 +60,41 @@
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  break;
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  }}
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+
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+
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  ```
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66
  ```ここに言語を入力
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+ kadai11_1.c: In function ‘f’:
68
+ kadai11_1.c:5:14: error: lvalue required as left operand of assignment
69
+ f(x) = x - cos(x);
70
+ ^
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+ kadai11_1.c: In function ‘df’:
72
+ kadai11_1.c:10:15: error: lvalue required as left operand of assignment
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+ df(x) = 1.0 + sin(x);
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+ ^
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+ kadai11_1.c: In function ‘main’:
58
- kadai11_1.c:4:5: warning: parameter names (without types) in function declaration
76
+ kadai11_1.c:16:5: warning: parameter names (without types) in function declaration
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  float f(x);
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78
  ^~~~~
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+ kadai11_1.c:16:11: error: conflicting types for ‘f’
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+ float f(x);
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+ ^
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+ kadai11_1.c:16:5: note: an argument type that has a default promotion can’t match an empty parameter name list declaration
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+ float f(x);
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+ ^~~~~
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+ kadai11_1.c:4:11: note: previous definition of ‘f’ was here
86
+ float f(float x){
87
+ ^
61
- kadai11_1.c:5:5: warning: parameter names (without types) in function declaration
88
+ kadai11_1.c:17:5: warning: parameter names (without types) in function declaration
62
89
  float df(x);
63
90
  ^~~~~
64
- kadai11_1.c:6:5: warning: data definition has no type or storage class
65
- f(x) = x - cos(x);
66
- ^
67
- kadai11_1.c:6:5: warning: type defaults to ‘int’ in declaration of ‘f’ [-Wimplicit-int]
68
- kadai11_1.c:6:5: warning: parameter names (without types) in function declaration
69
- kadai11_1.c:6:5: error: function ‘f’ is initialized like a variable
70
- kadai11_1.c:6:5: error: conflicting types for ‘f’
71
- kadai11_1.c:4:11: note: previous declaration of ‘f’ was here
72
- float f(x);
73
- ^
74
- kadai11_1.c:6:12: error: ‘x’ undeclared here (not in a function)
75
- f(x) = x - cos(x);
76
- ^
77
- kadai11_1.c:7:5: warning: data definition has no type or storage class
78
- df(x) = 1.0 + sin(x);
79
- ^~
80
- kadai11_1.c:7:5: warning: type defaults to ‘int’ in declaration of ‘df’ [-Wimplicit-int]
81
- kadai11_1.c:7:5: warning: parameter names (without types) in function declaration
82
- kadai11_1.c:7:5: error: function ‘df’ is initialized like a variable
83
- kadai11_1.c:7:5: error: conflicting types for ‘df’
91
+ kadai11_1.c:17:11: error: conflicting types for ‘df’
84
- kadai11_1.c:5:11: note: previous declaration of ‘df’ was here
85
92
  float df(x);
86
93
  ^~
87
- kadai11_1.c: In function ‘main’:
88
- kadai11_1.c:9:5: warning: parameter names (without types) in function declaration
94
+ kadai11_1.c:17:5: note: an argument type that has a default promotion can’t match an empty parameter name list declaration
89
- float f(x);
95
+ float df(x);
90
96
  ^~~~~
91
- kadai11_1.c:10:5: warning: parameter names (without types) in function declaration
97
+ kadai11_1.c:9:11: note: previous definition of ‘df’ was here
92
- float df(x);
98
+ float df(float x){
93
99
  ```
94
100
  のようなエラーが出てしまいました
Objective-CC++14

1

関数をmain外に記入

2022/06/28 07:29

投稿

yusuke.
yusuke.

スコア66

test CHANGED
File without changes
test CHANGED
@@ -29,4 +29,66 @@
29
29
 
30
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  のエラーが表示されています。どのように直したらよいのかわからないです。
31
31
 
32
+ 追記
33
+ main 外に書けばいいとの指摘をいただいたので書き直したところ
34
+ ```C
35
+ #include <stdio.h>
36
+ #include <math.h>
32
37
 
38
+ float f(x);
39
+ float df(x);
40
+ f(x) = x - cos(x);
41
+ df(x) = 1.0 + sin(x);
42
+ int main(){
43
+ float f(x);
44
+ float df(x);
45
+ float x;
46
+ int i;
47
+
48
+ x = 1.0;
49
+ for (i = 1; i <= 100;i++){;
50
+ x = x-f(x)/df(x);
51
+ if(fabs(f(x)) <= exp(-6));
52
+ printf("x=%f.\n",x);
53
+ break;
54
+ }}
55
+
56
+ ```
57
+ ```ここに言語を入力
58
+ kadai11_1.c:4:5: warning: parameter names (without types) in function declaration
59
+ float f(x);
60
+ ^~~~~
61
+ kadai11_1.c:5:5: warning: parameter names (without types) in function declaration
62
+ float df(x);
63
+ ^~~~~
64
+ kadai11_1.c:6:5: warning: data definition has no type or storage class
65
+ f(x) = x - cos(x);
66
+ ^
67
+ kadai11_1.c:6:5: warning: type defaults to ‘int’ in declaration of ‘f’ [-Wimplicit-int]
68
+ kadai11_1.c:6:5: warning: parameter names (without types) in function declaration
69
+ kadai11_1.c:6:5: error: function ‘f’ is initialized like a variable
70
+ kadai11_1.c:6:5: error: conflicting types for ‘f’
71
+ kadai11_1.c:4:11: note: previous declaration of ‘f’ was here
72
+ float f(x);
73
+ ^
74
+ kadai11_1.c:6:12: error: ‘x’ undeclared here (not in a function)
75
+ f(x) = x - cos(x);
76
+ ^
77
+ kadai11_1.c:7:5: warning: data definition has no type or storage class
78
+ df(x) = 1.0 + sin(x);
79
+ ^~
80
+ kadai11_1.c:7:5: warning: type defaults to ‘int’ in declaration of ‘df’ [-Wimplicit-int]
81
+ kadai11_1.c:7:5: warning: parameter names (without types) in function declaration
82
+ kadai11_1.c:7:5: error: function ‘df’ is initialized like a variable
83
+ kadai11_1.c:7:5: error: conflicting types for ‘df’
84
+ kadai11_1.c:5:11: note: previous declaration of ‘df’ was here
85
+ float df(x);
86
+ ^~
87
+ kadai11_1.c: In function ‘main’:
88
+ kadai11_1.c:9:5: warning: parameter names (without types) in function declaration
89
+ float f(x);
90
+ ^~~~~
91
+ kadai11_1.c:10:5: warning: parameter names (without types) in function declaration
92
+ float df(x);
93
+ ```
94
+ のようなエラーが出てしまいました
Objective-CC++14