/*
* This program source code file
* is part of KiCad, a free EDA CAD application.
*
* Copyright (C) 2020 <janvi@veith.net>
* Copyright (C) 2021-2022 KiCad Developers, see AUTHORS.txt for contributors.
*
* This program is free software: you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation, either version 3 of the License, or (at your
* option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <array>
#include <algorithm>
#include <limits>
#include "eseries.h"
/*
* If BENCHMARK is defined, any 4R E12 calculations will print its execution time to console
* My Hasswell Enthusiast reports 225 mSec what are reproducible within plusminus 2 percent
*/
//#define BENCHMARK
#ifdef BENCHMARK
#include <profile.h>
#endif
// Return a string from aValue (aValue is expected in ohms)
// If aValue < 1000 the returned string is aValue with unit = R
// If aValue >= 1000 the returned string is aValue/1000 with unit = K
// with notation similar to 2K2
// If aValue >= 1e6 the returned string is aValue/1e6 with unit = M
// with notation = 1M
static std::string strValue( double aValue )
{
std::string result;
if( aValue < 1000.0 )
{
result = std::to_string( static_cast<int>( aValue ) );
result += 'R';
}
else
{
double div = 1e3;
int unit = 'K';
if( aValue >= 1e6 )
{
div = 1e6;
unit = 'M';
}
aValue /= div;
int integer = static_cast<int>( aValue );
result = std::to_string(integer);
result += unit;
// Add mantissa: 1 digit, suitable for series up to E24
double mantissa = aValue - integer;
if( mantissa > 0 )
result += std::to_string( static_cast<int>( (mantissa*10)+0.5 ) );
}
return result;
}
E_SERIES::E_SERIES()
{
// Build the list of available resistor values in each En serie
double listValuesE1[] = { E1_VALUES };
double listValuesE3[] = { E3_VALUES };
double listValuesE6[] = { E6_VALUES };
double listValuesE12[] = { E12_VALUES };
double listValuesE24[] = { E24_VALUES };
// buildSeriesData must be called in the order of En series, because
// the list of series is expected indexed by En for the serie En
buildSeriesData( listValuesE1 );
buildSeriesData( listValuesE3 );
buildSeriesData( listValuesE6 );
buildSeriesData( listValuesE12 );
int count = buildSeriesData( listValuesE24 );
// Reserve a buffer for intermediate calculations:
// the buffer size is 2*count*count to store all combinaisons of 2 values
// there are 2*count*count = 29282 combinations for E24
int bufsize = 2*count*count;
m_combined_table.reserve( bufsize );
// Store predefined R_DATA items.
for( int ii = 0; ii < bufsize; ii++ )
m_combined_table.emplace_back( "", 0.0 );
}
int E_SERIES::buildSeriesData( const double aList[] )
{
double curr_decade = FIRST_VALUE;
int count = 0;
std::vector<R_DATA> curr_list;
for( ; ; )
{
double curr_r = LAST_VALUE;
for( int ii = 0; ; ii++ )
{
if( aList[ii] == 0.0 ) // End of list
break;
curr_r = curr_decade * aList[ii];
curr_list.emplace_back( strValue( curr_r ), curr_r );
count++;
if( curr_r >= LAST_VALUE )
break;
}
if( curr_r >= LAST_VALUE )
break;
curr_decade *= 10;
}
m_tables.push_back( std::move( curr_list ) );
return count;
}
void E_SERIES::Exclude( double aValue )
{
if( aValue != 0.0 ) // if there is a value to exclude other than a wire jumper
{
for( R_DATA& i : m_tables[m_series] ) // then search it in the selected E-Series table
{
if( i.e_value == aValue ) // if the value to exclude is found
i.e_use = false; // disable its use
}
}
}
void E_SERIES::simple_solution( uint32_t aSize )
{
uint32_t i;
m_results.at( S2R ).e_value = std::numeric_limits<double>::max(); // assume no 2R solution or max deviation
for( i = 0; i < aSize; i++ )
{
if( abs( m_combined_table.at( i ).e_value - m_required_value ) < abs( m_results.at( S2R ).e_value ) )
{
m_results[S2R].e_value = m_combined_table[ i ].e_value - m_required_value; // save signed deviation in Ohms
m_results[S2R].e_name = m_combined_table[ i ].e_name; // save combination text
m_results[S2R].e_use = true; // this is a possible solution
}
}
}
void E_SERIES::combine4( uint32_t aSize )
{
uint32_t i,j;
double tmp;
m_results[S4R].e_use = false; // disable 4R solution, until
m_results[S4R].e_value = m_results[S3R].e_value; // 4R becomes better than 3R solution
#ifdef BENCHMARK
PROF_TIMER timer; // start timer to count execution time
#endif
for( i = 0; i < aSize; i++ ) // 4R search outer loop
{ // scan valid intermediate 2R solutions
for( j = 0; j < aSize; j++ ) // inner loop combines all with itself
{
tmp = m_combined_table[i].e_value + m_combined_table[j].e_value; // calculate 2R+2R serial
tmp -= m_required_value; // calculate 4R deviation
if( abs( tmp ) < abs( m_results.at(S4R).e_value ) ) // if new 4R is better
{
m_results[S4R].e_value = tmp; // save amount of benefit
std::string s = "( ";
s.append( m_combined_table[i].e_name ); // mention 1st 2 component
s.append( " ) + ( " ); // in series
s.append( m_combined_table[j].e_name ); // with 2nd 2 components
s.append( " )" );
m_results[S4R].e_name = s; // save the result and
m_results[S4R].e_use = true; // enable for later use
}
tmp = ( m_combined_table[i].e_value * m_combined_table[j].e_value ) /
( m_combined_table[i].e_value + m_combined_table[j].e_value ); // calculate 2R|2R parallel
tmp -= m_required_value; // calculate 4R deviation
if( abs( tmp ) < abs( m_results[S4R].e_value ) ) // if new 4R is better
{
m_results[S4R].e_value = tmp; // save amount of benefit
std::string s = "( ";
s.append( m_combined_table[i].e_name ); // mention 1st 2 component
s.append( " ) | ( " ); // in parallel
s.append( m_combined_table[j].e_name ); // with 2nd 2 components
s.append( " )" );
m_results[S4R].e_name = s; // save the result
m_results[S4R].e_use = true; // enable later use
}
}
}
#ifdef BENCHMARK
printf( "Calculation time = %d mS", timer.msecs() );
fflush( 0 );
#endif
}
void E_SERIES::NewCalc()
{
for( R_DATA& i : m_combined_table )
i.e_use = false; // before any calculation is done, assume that
for( R_DATA& i : m_results )
i.e_use = false; // no combinations and no results are available
for( R_DATA& i : m_tables[m_series])
i.e_use = true; // all selected E-values available
}
uint32_t E_SERIES::combine2()
{
uint32_t combi2R = 0; // target index counts calculated 2R combinations
std::string s;
for( const R_DATA& i : m_tables[m_series] ) // outer loop to sweep selected source lookup table
{
if( i.e_use )
{
for( const R_DATA& j : m_tables[m_series] ) // inner loop to combine values with itself
{
if( j.e_use )
{
m_combined_table[combi2R].e_use = true;
m_combined_table[combi2R].e_value = i.e_value + j.e_value; // calculate 2R serial
s = i.e_name;
s.append( " + " );
m_combined_table[combi2R].e_name = s.append( j.e_name);
combi2R++; // next destination
m_combined_table[combi2R].e_use = true; // calculate 2R parallel
m_combined_table[combi2R].e_value = i.e_value * j.e_value / ( i.e_value + j.e_value );
s = i.e_name;
s.append( " | " );
m_combined_table[combi2R].e_name = s.append( j.e_name );
combi2R++; // next destination
}
}
}
}
return combi2R;
}
void E_SERIES::combine3( uint32_t aSize )
{
uint32_t j = 0;
double tmp = 0; // avoid warning for being uninitialized
std::string s;
m_results[S3R].e_use = false; // disable 3R solution, until 3R
m_results[S3R].e_value = m_results[S2R].e_value; // becomes better than 2R solution
for( const R_DATA& i : m_tables[m_series] ) // 3R Outer loop to selected primary E series table
{
if( i.e_use ) // skip all excluded values
{
for( j = 0; j < aSize; j++ ) // inner loop combines with all 2R intermediate
{ // results R+2R serial combi
tmp = m_combined_table[j].e_value + i.e_value;
tmp -= m_required_value; // calculate deviation
if( abs( tmp ) < abs( m_results[S3R].e_value ) ) // compare if better
{ // then take it
s = i.e_name; // mention 3rd component
s.append( " + ( " ); // in series
s.append( m_combined_table[j].e_name ); // with 2R combination
s.append( " )" );
m_results[S3R].e_name = s; // save S3R result
m_results[S3R].e_value = tmp; // save amount of benefit
m_results[S3R].e_use = true; // enable later use
}
tmp = i.e_value * m_combined_table[j].e_value /
( i.e_value + m_combined_table[j].e_value ); // calculate R + 2R parallel
tmp -= m_required_value; // calculate deviation
if( abs( tmp ) < abs( m_results[S3R].e_value ) ) // compare if better
{ // then take it
s = i.e_name; // mention 3rd component
s.append( " | ( " ); // in parallel
s.append( m_combined_table[j].e_name ); // with 2R combination
s.append( " )" );
m_results[S3R].e_name = s;
m_results[S3R].e_value = tmp; // save amount of benefit
m_results[S3R].e_use = true; // enable later use
}
}
}
}
// If there is a 3R result with remaining deviation consider to search a possibly better
// 4R solution
// calculate 4R for small series always
if( m_results[S3R].e_use && tmp )
combine4( aSize );
}
void E_SERIES::Calculate()
{
uint32_t no_of_2Rcombi = 0;
no_of_2Rcombi = combine2(); // combine all 2R combinations for selected E serie
simple_solution( no_of_2Rcombi ); // search for simple 2 component solution
if( m_results[S2R].e_value ) // if simple 2R result is not exact
combine3( no_of_2Rcombi ); // continiue searching for a possibly better solution
strip3();
strip4();
}
void E_SERIES::strip3()
{
std::string s;
if( m_results[S3R].e_use ) // if there is a 3 term result available
{ // what is connected either by two "|" or by 3 plus
s = m_results[S3R].e_name;
if( ( std::count( s.begin(), s.end(), '+' ) == 2 )
|| ( std::count( s.begin(), s.end(), '|' ) == 2 ) )
{ // then strip one pair of braces
s.erase( s.find( '(' ), 1 ); // it is known sure, this is available
s.erase( s.find( ')' ), 1 ); // in any unstripped 3R result term
m_results[S3R].e_name = s; // use stripped result
}
}
}
void E_SERIES::strip4()
{
std::string s;
if( m_results[S4R].e_use ) // if there is a 4 term result available
{ // what are connected either by 3 "+" or by 3 "|"
s = m_results[S4R].e_name;
if( ( std::count( s.begin(), s.end(), '+' ) == 3 )
|| ( std::count( s.begin(), s.end(), '|' ) == 3 ) )
{ // then strip two pair of braces
s.erase( s.find( '(' ), 1 ); // it is known sure, they are available
s.erase( s.find( ')' ), 1 ); // in any unstripped 4R result term
s.erase( s.find( '(' ), 1 );
s.erase( s.find( ')' ), 1 );
m_results[S4R].e_name = s; // use stripped result
}
}
}