private static string ConstructCurrentDeciphering(string[] selections,
int[] selectionShifts)
{
string[] currentSelections = new string[selections.Length];
for (int i = 0; i < currentSelections.Length; i++)
{
currentSelections[i] = FrequencyAnalysis.DecipherTextByMapping(selections[i],
ProgramMath.GetCharacterMappingByCaesarCipherOffset(selectionShifts[i]));
}
return(FrequencyAnalysis.ReconstructTextFromOffsetSelections(currentSelections));
}
public static Dictionary <char, char> GetOptimalCharacterMapping(Dictionary <char, double> textCharProportion,
Dictionary <char, double> targetCharProportion,
out double mappingDifference,
out int mappingShiftAmount)
{
/*Mappings are { inputTextChar : actualChar }*/
double minDifference = double.MaxValue;
Dictionary <char, char> optimalMapping = null;
int optimalShiftAmount = 0;
for (int i = 0; i < 26; i++)
{
/*Create Character Mapping*/
Dictionary <char, char> mapping = ProgramMath.GetCharacterMappingByCaesarCipherOffset((26 - i) % 26);
/*Test character mapping*/
Dictionary <char, double> mappedCharProportions = new Dictionary <char, double>();
foreach (char key in textCharProportion.Keys)
{
mappedCharProportions[mapping[key]] = textCharProportion[key];
}
double difference = ProgramMath.GetKeyFrequencyDifference(mappedCharProportions, targetCharProportion);
/*Compare mapping to best*/
if (difference < minDifference)
{
minDifference = difference;
optimalMapping = new Dictionary <char, char>(mapping);
optimalShiftAmount = i;
}
}
mappingDifference = minDifference;
mappingShiftAmount = optimalShiftAmount;
return(optimalMapping);
}