LAr supercell data are received by the gFEX in a 10-bit multi-linear encoded form. More...

#include <gFEXCompression.h>

Collaboration diagram for LVL1::gFEXCompression:

Static Public Member Functions
static unsigned int	compress (float Energy)
	Compress data. More...

static int	expand (unsigned int code)
	Uncompress data. More...

static unsigned int	threshold (unsigned int code, int threshold=-101200)
	Apply threshold to compressed data. More...

static unsigned int	linearize (unsigned int code, int threshold=0)
	Linearize LAr code to eFEX internal format. More...

Static Private Attributes
static const int	s_maxET = 1019200
	Maximum ET value that can be encoded. More...

static const unsigned int	s_nRanges = 6
	Number of ranges. More...

static const int	s_steps [s_nRanges] = {12800, 50, 25, 50, 100, 25600}
	Step sizes in each range, MeV. More...

static const int	s_minET [s_nRanges] = {-101200, -50000, -12800, 12800, 51200, 200000}
	Minimum ET values in each range, MeV. More...

static const int	s_minCode [s_nRanges] = {2, 6, 750, 1774, 2542, 4030}
	Minimum code value in each range. More...

static const int	s_NoData = 0
	Indicates no data present. More...

static const unsigned int	s_LArUnderflow = 1
	LAr underflow code. More...

static const unsigned int	s_LArOverflow = 4062
	LAr overflow code. More...

static const unsigned int	s_LArReserved_min = 4063
	Reserved code min value. More...

static const unsigned int	s_LArReserved_max = 4094
	Reserved code max value. More...

static const unsigned int	s_LArInvalid = 4095
	Invalid code value. More...

static const unsigned int	s_LArMaxCode = 4095
	LAr saturated code. More...

static const unsigned int	s_gFEXstep = 200
	L1Calo ET digit step. More...

static const unsigned int	s_gFEXOverflow = 0xffff
	L1Calo saturated/overflow. More...

static const int	s_error = -999
	Error return value. More...

Detailed Description

LAr supercell data are received by the gFEX in a 10-bit multi-linear encoded form.

This simple utility class contains 3 functions:

Compress: encodes a signed integer MeV value
Expand: decodes a 10 bit unsigned int into a signed integer MeV value
Threshold: applies a threshold (in MeV) to the compressed code, zeroing if below
Linearize: decodes a 10 bit unsigned int into the unsigned 16 bit gFEX ET with least count of 25 MeV. A user-defined threshold (in MeV) can be applied, but as the gFEX ET is positive a negative threshold is equivalent to a threshold of 0.

Definition at line 26 of file gFEXCompression.h.

Member Function Documentation

◆ compress()

unsigned int LVL1::gFEXCompression::compress ( float Energy )

static

Compress data.

Definition at line 20 of file gFEXCompression.cxx.

                                                     {
  
     int Et = std::round(floatEt);
  
     // Check for overflow
     if (Et >= s_maxET) return s_LArOverflow;
  
     // Find which range the ET value is in
     int range = -1;
     for (unsigned int i = 0; i < s_nRanges; i++) {
         if (Et < s_minET[i]) break;
         range = i;
     }
  
     // Calculate code
     unsigned int code = 0;
  
     if (range < 0) {
         // Below minimum value
         code = s_LArUnderflow;
     }
     else {
         // Lies inside one of the value ranges
         int steps = (Et - s_minET[range])/s_steps[range];
         code = s_minCode[range] + steps;
     }
  
     return code;
 }

◆ expand()

int LVL1::gFEXCompression::expand ( unsigned int code )

static

Uncompress data.

Now expand code into an ET value. Start by finding what range the code is in

Now expand the value

Definition at line 50 of file gFEXCompression.cxx.

                                              {
  
   // Deal with special codes first:
   if (code == s_NoData)  return 0;
   if (code == s_LArInvalid || (code > s_LArReserved_min && code < s_LArReserved_max) || code > s_LArMaxCode) return s_error;
   if (code == s_LArOverflow ) return s_maxET;
  
   int range = 0;
   for (unsigned int i = 0; i < s_nRanges-1; ++i) {
     if (code < (unsigned int)s_minCode[i+1]) break;
     range++;
   }
   int Et = s_minET[range] + (code-s_minCode[range])*s_steps[range];
  
   return Et;
 }

◆ linearize()

unsigned int LVL1::gFEXCompression::linearize	(	unsigned int	code,
		int	threshold = `0`
	)

static

Linearize LAr code to eFEX internal format.

Apply the threshold. Since eFEX ET is positive, minimum threshold is 0.

Expand the ET value

Convert to eFEX digit scale

Definition at line 83 of file gFEXCompression.cxx.

                                                                         {
  
   if (threshold < 0) threshold = 0;
   code = gFEXCompression::threshold(code, threshold);
  
   int Et = gFEXCompression::expand(code);
  
   // Check for overflow
   if (Et >= s_maxET) return s_gFEXOverflow;
  
   unsigned int gFexET = Et/s_gFEXstep;
   return gFexET;
 }

◆ threshold()

unsigned int LVL1::gFEXCompression::threshold	(	unsigned int	code,
		int	threshold = `-101200`
	)

static

Apply threshold to compressed data.

Convert threshold into a compressed code

Code zero if < threshold

Definition at line 71 of file gFEXCompression.cxx.

                                                                         {
  
   unsigned int cut = gFEXCompression::compress(threshold);
  
   if (code < cut) code = 0;
  
   return code;
 }

Member Data Documentation

◆ s_error

const int LVL1::gFEXCompression::s_error = -999

staticprivate

Error return value.

Definition at line 70 of file gFEXCompression.h.

◆ s_gFEXOverflow

const unsigned int LVL1::gFEXCompression::s_gFEXOverflow = 0xffff

staticprivate

L1Calo saturated/overflow.

Definition at line 68 of file gFEXCompression.h.

◆ s_gFEXstep

const unsigned int LVL1::gFEXCompression::s_gFEXstep = 200

staticprivate

L1Calo ET digit step.

Definition at line 66 of file gFEXCompression.h.

◆ s_LArInvalid

const unsigned int LVL1::gFEXCompression::s_LArInvalid = 4095

staticprivate

Invalid code value.

Definition at line 60 of file gFEXCompression.h.

◆ s_LArMaxCode

const unsigned int LVL1::gFEXCompression::s_LArMaxCode = 4095

staticprivate

LAr saturated code.

Maximum code value

Definition at line 64 of file gFEXCompression.h.

◆ s_LArOverflow

const unsigned int LVL1::gFEXCompression::s_LArOverflow = 4062

staticprivate

LAr overflow code.

Definition at line 54 of file gFEXCompression.h.

◆ s_LArReserved_max

const unsigned int LVL1::gFEXCompression::s_LArReserved_max = 4094

staticprivate

Reserved code max value.

Definition at line 58 of file gFEXCompression.h.

◆ s_LArReserved_min

const unsigned int LVL1::gFEXCompression::s_LArReserved_min = 4063

staticprivate

Reserved code min value.

Definition at line 56 of file gFEXCompression.h.

◆ s_LArUnderflow

const unsigned int LVL1::gFEXCompression::s_LArUnderflow = 1

staticprivate

LAr underflow code.

Definition at line 52 of file gFEXCompression.h.

◆ s_maxET

const int LVL1::gFEXCompression::s_maxET = 1019200

staticprivate

Maximum ET value that can be encoded.

Definition at line 40 of file gFEXCompression.h.

◆ s_minCode

const int LVL1::gFEXCompression::s_minCode = {2, 6, 750, 1774, 2542, 4030}

staticprivate

Minimum code value in each range.

Definition at line 48 of file gFEXCompression.h.

◆ s_minET

const int LVL1::gFEXCompression::s_minET = {-101200, -50000, -12800, 12800, 51200, 200000}

staticprivate

Minimum ET values in each range, MeV.

Definition at line 46 of file gFEXCompression.h.

◆ s_NoData

const int LVL1::gFEXCompression::s_NoData = 0

staticprivate

Indicates no data present.

Definition at line 50 of file gFEXCompression.h.

◆ s_nRanges

const unsigned int LVL1::gFEXCompression::s_nRanges = 6

staticprivate

Number of ranges.

Definition at line 42 of file gFEXCompression.h.

◆ s_steps

const int LVL1::gFEXCompression::s_steps = {12800, 50, 25, 50, 100, 25600}

staticprivate

Step sizes in each range, MeV.

Definition at line 44 of file gFEXCompression.h.

The documentation for this class was generated from the following files:

Static Public Member Functions

Static Private Attributes

Detailed Description

Member Function Documentation

◆ compress()

◆ expand()

◆ linearize()

◆ threshold()

Member Data Documentation

◆ s_error

◆ s_gFEXOverflow

◆ s_gFEXstep

◆ s_LArInvalid

◆ s_LArMaxCode

◆ s_LArOverflow

◆ s_LArReserved_max

◆ s_LArReserved_min

◆ s_LArUnderflow

◆ s_maxET

◆ s_minCode

◆ s_minET

◆ s_NoData

◆ s_nRanges

◆ s_steps