# Storing 0.07 as a double - impossible???

175

Is it just me, or can 0.07 not be stored accurately?

Example

```double number=0.07;
Comment(number);```

This displays as 0.07000000000000001, therefore I can for instance send an order using a lot size of 0.07.

1401

Well, you can try ...

`Comment(NormalizeDouble(number,2));`
175

First thing I tried. Doesn't help at all.

I've even wrote my own normalise function that didn't help either.

This makes the following command impossible, even though it's perfectly valid

`OrderSend(Symbol(),OP_BUY,0.07,Ask,3,0,0,NULL,0,0,CLR_NONE);`
1401

```double number=0.07;

It works for me.
Moderator
2330

Paul_B:

First thing I tried. Doesn't help at all.

I've even wrote my own normalise function that didn't help either.

This makes the following command impossible, even though it's perfectly valid

What is minlot and lotstep for your broker?

Moderator
10569

Paul_B:

First thing I tried. Doesn't help at all.

I've even wrote my own normalise function that didn't help either.

This makes the following command impossible, even though it's perfectly valid

`OrderSend(Symbol(),OP_BUY,0.07,Ask,3,0,0,NULL,0,0,CLR_NONE);`

The OrderSend will work perfectly fine with the constant 0.07, it is only when it is calculated that there might be a problem

ie

```double a=1.4;
double b=2.0;
double lotsize =a/b;

May or may not work as intended

15577

Paul_B: Is it just me, or can 0.07 not be stored accurately?
1. Correct, it can not be stored accurately - because 1/10 is not a multiple of powers of two. 1/8 can be. See http://en.wikipedia.org/wiki/Single-precision_floating-point_format (Ex 2: Consider a value 0.25)
2.  Do NOT use NormalizeDouble, EVER. For ANY Reason. It's a kludge, don't use it. It's use is always wrong. Wrong as given here:deysmacro: Well, you can try ...`Comment(NormalizeDouble(number,2));`Taking a double, normalizing it to 2 digits, give you a double - same problem - does nothing.
3. `Comment(DoubleToString(number,2));`

1401

WHRoeder:
1.  Do NOT use NormalizeDouble, EVER. For ANY Reason. It's a kludge, don't use it. It's use is always wrong. Wrong as given here:deysmacro: Well, you can try ...Taking a double, normalizing it to 2 digits, give you a double - same problem - does nothing

It's not like I don't see that coming long before I post it.

Moderator
32411

deysmacro:

It's not like I don't see that coming long before I post it.

Don't worry, NormalizeDouble works perfectly for what is intended.