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Is there way to convert float from 32bit integer? [closed]

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using c#
the float value i need to read
= 24.500000
when i try to read i get this result
= 1103364096
what conversion should i do to get the real value? i need help on this.
my failed attempts:
int data_1 = 1103364096;
UInt16 value = (UInt16)x;
ushort data_2= (ushort)(1103364096 & ((1 << 16) - 1));
int r = 1103364096;
short trimmed = unchecked((short)r);
these don't work!

As suggested by Jeremy, you need to use BitConverter.
We'll first get the byte representation of the integer i, then interpret those bytes as a float:
int i = 1103364096;
byte[] b = BitConverter.GetBytes(i);
float f = BitConverter.ToSingle(b, 0);
Console.WriteLine(f); // outputs 24.5
Try it online

Use Convert.ToFloat(x) to convert (from anything) to a float.
Use Convert.ToInt32(x) to convert (from anything) to an Int32.

Equivalent of a C# byte[] in php? [closed]

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What is the equivalent of c#'s
byte[] buffer = File.ReadAllBytes(openFileDialog1.FileName);
in php?
Should I use file_read_contents(file) and then unpack the string into byte array?

I have zero experience in C# but I think what you're looking for is something like this
<?php
$file = fopen("file.txt","r");
while (! feof ($file))
echo fgetc($file);
fclose($file);

Your answer isn't very clear, I think you mean reading file as an array of bytes.
You can use unpack() function for this purpose:
$filename = "myFile.txt";
$handle = fopen($filename, "rb");
$fsize = filesize($filename);
$contents = fread($handle, $fsize);
$byteArray = unpack("N*",$contents);
print_r($byteArray);
for($n = 0; $n < 16; $n++)
{
echo $byteArray [$n].'<br/>';
}
otherwise you can get at the individual bytes similar to how you would in C:
$data = file_get_contents("myFile.txt");
for($i = 0; $i < strlen($data); ++$i) {
$char = $data[$i];
echo "Byte $i: $char\n";
}

Fastest way to read binary representation of data [closed]

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I am trying to read a file (>150 mb) and I need to read the binary representation of that file.
The file type is a .MP4.
I am trying to use this:
string.Join("-", x.Select(byt => Convert.ToString(byt, 2).PadLeft(8, '0')));
but the problems are:
1) It is too slow
2) It uses a lot of RAMs memory
If I read the raw bytes with
File.ReadAllBytes(path);
How Can I do that without having to convert the file into a string (method below)?

When working with big files like in your case, it would be better to just view a small part of the file (It's not like you can show the entire file at once anyhow).
Some Streams (like the FileStream) have the ability to Seek a certain position, which you can use to set your starting position.
if(position > _stream.Length)
throw new IndexOutOfRangeException();
if (position + length > _stream.Length)
length = (int) (_stream.Length - position);
_stream.Seek(position, SeekOrigin.Begin);
_stream.Read(buffer, 0, length);
The conversion to binary isn't that hard eiter, depending on the bit order you want, you'll probably have to reverse this (this is highest bit left 1 = 00000001). To gain some performance when building the string, use a StringBuilder instead of just concating strings with += or +.
public string ToBinary(byte value)
{
string result = "";
for (int i = 0; i < 8; i++)
{
result = value%2 + result;
value /= 2;
}
return result;
}
private string ToBinary(byte[] values)
{
StringBuilder builder = new StringBuilder();
int column = 0;
foreach (byte value in values)
{
builder.Append(ToBinary(value) + " ");
column++;
if (column == 8)
{
builder.AppendLine();
column = 0;
}
}
return builder.ToString();
}
Can can then eiter use it in a console application
https://dotnetfiddle.net/GVLm27
or put those two together with a TextBox and a ScrollBar and you have a good starting point:
ong position = (long) scrollBar1.Value;
byte[] data = new byte[128];
_file.GetSection(data, position, data.Length);
textBox1.Text = ToBinary(data);
After all those comments on your question I hope the original title is still what you are after
C# Fastest way to read binary representation of data

Converting a String to hex and calculate binary result in python [closed]

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I got stuck with my code, tried anything on this side and many other things Google showed.
To the problem:
I try to convert some code-snips from C# to phyton, but on this special point i got stuck.
public static long decode(string data, int size, int offset = 0)
{
long value = 0;
for (int i = 0; i < size; ++i) {
value <<= 6;
value |= (long)data[offset + i] - 0x30;
}
return value;
}
The String Data could be something like 1Dh. Based on this I convert each char to the hex-equivalent: 0x31, 0x44, 0x68 and subtract 0x30; so I get 0x1, 0x14, 0x38;
In the next step I have to convert to the binary equivalent 000001, 010100, 111000 and merge this to
000001010100111000. From this I want to get the integer meaning, in this case 5432.
Is there a possibility to do this in a smart and easy way in python?

It's actually pretty easy, and the translation is pretty straight forward. You can continue to use your bit shifting. The only change is the syntax of for-loop and using ord() to get the integer value from a character.
def decode(data, size, offset=0):
value = 0
for ch in data[offset:size]:
value <<= 6
value |= ord(ch) - 0x30
return value
Running this in the interpreter, I get 5432:
>>> decode("1Dh", 3)
5432

How to gain memory consumption for array a with n rows and m columns? [closed]

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How to get the allocated space in memory for array A with N rows and M columns in C# ?
is there any function or something like this ?
I search several times in internet; but i can't find any good answer for my question that i understand that.

If you want to know that how much memory a two dimensional array will consume, then it will depend on the data type.
e.g. if you have an array of 3 rows and 4 columns with type int then as an int consumes 32 bit or 4 bytes. So whole array will consume 32*3*4 = 384 bits or 4*4*3 = 48 bytes.
For simple calculation you can use following code for getting the memory consumption by different value types:
var size = BitConverter.GetBytes(value).Length; // here value can be any value type.

You can't know the exact size occupied in memory by the entire array with all mem-paddings and etc. You can use the following approach to estimate of how many bytes in memory occupied by all array cells.:
long size1 = GetArrayElementsSizeInMemory(new int[] { 1, 2 }); // 8 bytes
long size2 = GetArrayElementsSizeInMemory(new int[,] { { 1 }, { 2 }, { 3 } }); // 12 bytes
long size3 = GetArrayElementsSizeInMemory(new int[][] { new int[] { 1, 2 }, new int[] { 3, 4 } }); // 16 bytes
//...
static long GetArrayElementsSizeInMemory(Array array) {
return array.Length * GetArrayElementSize(array);
}
static long GetArrayElementSize(Array array) {
var elemenType = array.GetType().GetElementType();
return elemenType.IsValueType ? Marshal.SizeOf(elemenType) : IntPtr.Size;
}