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Small problem with printing float array elements.

Feb 23, 2015 at 2:53pm
notwittyusername (16)
Doing a school assignment where I have to read weight and put them in an array. Our teacher insists we use float as the data type as weight can sometimes be in decimals, too.
Why am I getting:

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Enter the name: asd

Enter the weight: 23

Enter the name: de

Enter the weight: 45

Enter the name: as

Enter the weight: 55

Name: asd
Weight: 2.8026e-45

Name: de
Weight: 0

Name: as
Weight: 5.88323e-39

These numbers as output when I want to output the exact number read by the compiler?


Here's the code:
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  #include<iostream>
using namespace std;
int main()
{
	float weight[4], f_weight=0.0;
	string name[4], s_name;
	for(int i=0;i<3;i++)
	{
		cout<< endl << "Enter the name: ";
		cin>>s_name;
		name[i]=s_name;
		cout<< endl << "Enter the weight: ";
		cin>>f_weight;
		if(f_weight < 15 or f_weight > 150)
		{
			cout<< "Invalid input. Please enter weight again: ";
			cin>>f_weight;
		}
		
	}
	for(int k=0;k<3;k++)
	{
		cout<< endl << "Name: " << name[k] << endl;
		cout<< "Weight: " << weight[k] << endl;
	}
	system("PAUSE");
}
Edit & run on cpp.sh
Last edited on Feb 23, 2015 at 2:55pm
Feb 23, 2015 at 2:58pm
Texan40 (645)
You may want to look at std::fixed and std::setprecision (iomanip). These let you print floating point and double precision numbers in a more easy to read format.
Feb 23, 2015 at 3:03pm
TarikNeaj (2580)
if(f_weight < 15 or f_weight > 150)

the "or" doesnt work that way. If you want to say "or" you do it using these ||

if(f_weight < 15 || f_weight > 150)
Feb 23, 2015 at 3:08pm
notwittyusername (16)
@Texan40

Isn't there a simpler way to do it or should I refrain from using float completely?

@TarikNeaj

The pipe? I've been using it but I find using 'or' better, I don't think there's any difference between the two at all, both work the same way.
Feb 23, 2015 at 3:12pm
TarikNeaj (2580)
Here is how I would have written the program - 

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        float weight[3];
	string name[3];

		for (int i = 0; i<3; i++)
		{
			cout << "Enter the name: ";
			cin >> name[i];

			cout << endl << "Enter the weight: ";
			cin >> weight[i];
			cout << endl;

			if (weight[i] < 15 || weight[i] > 150)
			{
				cout << "Invalid input. Please enter weight again: ";
				cin >> weight[i];
			}


		}
		
		for (int k = 0; k < 3; k++)
		{
			cout << endl << "Name: " << name[k] << endl;
			cout << "Weight: " << weight[k] << endl;
		}


Here is how I would have written the program. Compare it to yours, try and understand what Ive done.
Feb 23, 2015 at 3:17pm
notwittyusername (16)
The last time I used the array element in a selection the compiler gave an error, I must've been using it wrong. It still doesn't solve the main problem, though.
Last edited on Feb 23, 2015 at 3:17pm
Feb 23, 2015 at 3:20pm
TarikNeaj (2580)
Could you post the code again with some of the changes you've made?
Feb 23, 2015 at 3:24pm
notwittyusername (16)
Nevermind, I'm an idiot. It's fixed. I'm not sure why removing the separate variables from the code fixed it.
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