ios - How to turn 4 bytes into a float in objective-c from NSData -

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here example of turning 4 bytes 32bit integer in objective-c. function readint grabs 4 bytes read function , converts single 32 bit int. know how convert 4 bytes float? believe big endian. need readfloat function. can never grasp these bitwise operations.

edit: i forgot mention original data comes java's dataoutputstream class. writefloat function accordign java doc is

converts float argument int using floattointbits method in class float, , writes int value underlying output stream 4-byte quantity, high byte first.

this objective c trying extract data written java. 

- (int32_t)read{     int8_t v;     [data getbytes:&v range:nsmakerange(length,1)];     length++;     return ((int32_t)v & 0x0ff); }  - (int32_t)readint {     int32_t ch1 = [self read];     int32_t ch2 = [self read];     int32_t ch3 = [self read];     int32_t ch4 = [self read];     if ((ch1 | ch2 | ch3 | ch4) < 0){         @throw [nsexception exceptionwithname:@"exception" reason:@"eofexception" userinfo:nil];     }     return ((ch1 << 24) + (ch2 << 16) + (ch3 << 8) + (ch4 << 0)); }

[data getbytes:&myfloat range:nsmakerange(locationwherefloatstarts, sizeof(float)] ought trick.


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