digitalmars.D.learn - Why am I getting a dividing by zero error message
- Ruby The Roobster (76/76) Jan 28 2021 Here is the output/input of the program:
- jmh530 (4/9) Jan 28 2021 It might help to separate break this out into smaller functions.
- Dennis (5/10) Jan 28 2021 Here you set data[0].y to 0
- Ruby The Roobster (3/13) Jan 28 2021 Okay. That worked. I added a check to set temp to zero if tempa
- Ruby The Roobster (3/22) Jan 28 2021 Instead of dividing, which causes the bug.
- evilrat (8/71) Jan 28 2021 /*
- tsbockman (17/53) Jan 28 2021 1) Outside the loops, you set `data[0] = (new Egg(0, 0, "a"))`
Here is the output/input of the program:
Type in data for an egg:
Width: 3
Hight: 2
object.Error (0): Integer Divide by Zero
----------------
0x004023FE
0x0040CF9F
0x0040CF19
0x0040CDB4
0x00409033
0x00402638
0x75F86359 in BaseThreadInitThunk
0x77018944 in RtlGetAppContainerNamedObjectPath
0x77018914 in RtlGetAppContainerNamedObjectPath
Chicken:
Here is the source code:
import std.stdio;
import std.string;
void main(){
egg[1000] data;
data[0] = (new egg(0,0,"a"));
for(int i = 1;i<1000;i++)
{
int tempx;
int tempy;
string tempz;
int high = 0;
double highs = 0;
writeln("Type in data for an egg:");
write("Width: ");
readf(" %d",&tempx);
write("Hight: ");
readf(" %d",&tempy);
write("Chicken: ");
tempz = readln();
data[i] = new egg(tempx,tempy,tempz);
for(int x = 0;x < i;x++)
{
int tempa;
int tempb;
double temp;
tempa = data[x].x;
if(tempa < 0)
tempa-=tempa;
tempb = data[x].y;
if(tempb < 0)
tempb-=tempb;
temp = tempa / tempb;
if(temp > highs)
{
highs = temp;
high = x;
}
}
tempx = data[high].x - data[i].x;
if(tempx < 0)
tempx-=tempx;
tempy = data[high].y - data[i].y;
if(tempy < 0)
tempy-=tempy;
}
}
class egg {
public:
this(uint x,uint y,string name)
{
this.x = x;
this.y = y;
name = cast(string)name;
}
uint x;
uint y;
char[] name;
}
Why is this happening? Does anybody know?
Jan 28 2021
jmh530 <john.michael.hall gmail.com> On Thursday, 28 January 2021 at 18:37:37 UTC, Ruby The Roobster wrote:Here is the output/input of the program: Type in data for an egg: Width: 3 Hight: 2 [...]It might help to separate break this out into smaller functions. May make it easier to follow what is happening.
Jan 28 2021
On Thursday, 28 January 2021 at 18:37:37 UTC, Ruby The Roobster wrote:object.Error (0): Integer Divide by Zero Why is this happening? Does anybody know?data[0] = (new egg(0,0,"a"));Here you set data[0].y to 0tempb = data[x].y;In the first iteration, this equals data[0].y which equals 0temp = tempa / tempb;And then you divide by zero here, hence the error
Jan 28 2021
On Thursday, 28 January 2021 at 18:53:51 UTC, Dennis wrote:On Thursday, 28 January 2021 at 18:37:37 UTC, Ruby The Roobster wrote:Okay. That worked. I added a check to set temp to zero if tempa or tempb is zero.object.Error (0): Integer Divide by Zero Why is this happening? Does anybody know?data[0] = (new egg(0,0,"a"));Here you set data[0].y to 0tempb = data[x].y;In the first iteration, this equals data[0].y which equals 0temp = tempa / tempb;And then you divide by zero here, hence the error
Jan 28 2021
On Thursday, 28 January 2021 at 18:56:45 UTC, Ruby The Roobster wrote:On Thursday, 28 January 2021 at 18:53:51 UTC, Dennis wrote:Instead of dividing, which causes the bug.On Thursday, 28 January 2021 at 18:37:37 UTC, Ruby The Roobster wrote:Okay. That worked. I added a check to set temp to zero if tempa or tempb is zero.object.Error (0): Integer Divide by Zero Why is this happening? Does anybody know?data[0] = (new egg(0,0,"a"));Here you set data[0].y to 0tempb = data[x].y;In the first iteration, this equals data[0].y which equals 0temp = tempa / tempb;And then you divide by zero here, hence the error
Jan 28 2021
On Thursday, 28 January 2021 at 18:37:37 UTC, Ruby The Roobster wrote:Here is the output/input of the program: Type in data for an egg: Width: 3 Hight: 2 object.Error (0): Integer Divide by Zero ---------------- 0x004023FE 0x0040CF9F 0x0040CF19 0x0040CDB4 0x00409033 0x00402638 0x75F86359 in BaseThreadInitThunk 0x77018944 in RtlGetAppContainerNamedObjectPath 0x77018914 in RtlGetAppContainerNamedObjectPath Chicken: Here is the source code: import std.stdio; import std.string; void main(){ egg[1000] data; data[0] = (new egg(0,0,"a")); for(int i = 1;i<1000;i++) { int tempx; int tempy; string tempz; int high = 0; double highs = 0; writeln("Type in data for an egg:"); write("Width: "); readf(" %d",&tempx); write("Hight: "); readf(" %d",&tempy); write("Chicken: "); tempz = readln(); data[i] = new egg(tempx,tempy,tempz); for(int x = 0;x < i;x++) { int tempa; int tempb; double temp; tempa = data[x].x; if(tempa < 0) tempa-=tempa; tempb = data[x].y; if(tempb < 0) tempb-=tempb;/* x starts with 0, you are acessing data[x] which is set to egg(0,0,"a") and you get div by zero as a result. I see logic error, though I might be wrong because I haven't actually run your code. */temp = tempa / tempb; if(temp > highs) { highs = temp; high = x; } } tempx = data[high].x - data[i].x; if(tempx < 0) tempx-=tempx; tempy = data[high].y - data[i].y; if(tempy < 0) tempy-=tempy; } }
Jan 28 2021
On Thursday, 28 January 2021 at 18:37:37 UTC, Ruby The Roobster
wrote:
Here is the output/input of the program:
Type in data for an egg:
Width: 3
Hight: 2
object.Error (0): Integer Divide by Zero
...
Here is the source code:
import std.stdio;
import std.string;
void main(){
egg[1000] data;
data[0] = (new egg(0,0,"a"));
for(int i = 1;i<1000;i++)
{
...
data[i] = new egg(tempx,tempy,tempz);
for(int x = 0;x < i;x++)
{
int tempa;
int tempb;
double temp;
tempa = data[x].x;
if(tempa < 0)
tempa-=tempa;
tempb = data[x].y;
if(tempb < 0)
tempb-=tempb;
temp = tempa / tempb;
if(temp > highs)
{
highs = temp;
high = x;
}
}
...
Why is this happening? Does anybody know?
1) Outside the loops, you set `data[0] = (new Egg(0, 0, "a"))`
2) The outer `for(int i` loop, starts at `i = 1`, and so it never
overwrites the work of step (1).
3) The inner `for(int x` loop starts at `x = 0`, so its first
pass divides by `data[1].y`. Since you set that field equal to 0
in step (1), and both operands have type `uint`, the result is a
divide by zero error.
4) Also, `if(tempb < 0) tempb-=tempb;` will convert any negative
values into zeroes. Maybe you meant to write `if(tempb < 0) tempb
= -tempb;` to get the absolute value, instead?
There are many ways you could fix the program. (I won't try to
guess what the best way is, though, because it's not entirely
clear to me what this program is actually intended to do. As is,
it does some calculations, but doesn't try to output their
results in any way.)
Jan 28 2021