markov_chain1.Rmd

---
title: "Markov Chain Music"
output: html_notebook
---


This is an [R Markdown](http://rmarkdown.rstudio.com) Notebook. When you execute code within the notebook, the results appear beneath the code. 
Try executing this chunk by clicking the *Run* button within the chunk or by placing your cursor inside it and pressing *Cmd+Shift+Enter*. 

```{r setup}
library(reticulate)
library(tidyverse)
#library(markovchain) did not work correctly unfortunately
```



```{python general prep - song selection}
from music21 import *
import pandas as pd

s2 = converter.parse('/Users/alk/Downloads/Akkord.mid')
partStream = s2.parts.stream()

print("List of instruments and time signatures found on MIDI file:") #gets us instruments
  for p in partStream:
      print (p.partName)
      print(list(p[meter.TimeSignature]))
      
partlist = list([p.partName for p in partStream])
tempolist = list(s2.metronomeMarkBoundaries())

def teilDaten(k, myStream): #k for the part and myStream and object like parts.stream()
    s32 = list([note.fullName for note in myStream[k].recurse().notesAndRests])
    s34 = list([note.quarterLength for note in myStream[k].recurse().notesAndRests])
  
    diemusik = pd.DataFrame({'AllThings':s32,'dauer':s34} )
    return diemusik

print("Over to R")

#abc = teilDaten(0, partStream) just a test
```



```{r }
m21 <- reticulate::import('music21')


instrumente <- py$partlist #check the instruments and modify them to fit music21 instruments list https://web.mit.edu/music21/doc/moduleReference/moduleInstrument.html
#instrumente[1] <-"StringInstrument"; instrumente[2] <-"StringInstrument"; instrumente[3] <-"Piano"; instrumente[4] <-"Bass"; #Keep in mind R starts with 1 Python 0 Midi 1
print(instrumente)

instrumente[1] <- "Piano";# instrumente[2] <- "Piano"

print(py$tempolist) #print to get tempo markings, choose 1 for convenience

original <- py$s2
bach <- original$parts$stream() 



k <- 0L # L after number to ensure integer not float
```


```{r Functions for n1 and n2}
CreatePart <- function(transition_markov,sl,k){
  i <- 1
  ms <- m21$stream$Measure()
  temps<- c("n1", "dur", "oct", "pit")
  
  while(i <= sl) {
    past <- current
    current  <- sample(uniques$AllThings, 1, prob = transition_markov[past,])
    
    if(word(current,-1) == 'Note'|| word(current,1)== 'Chord'){
      
      
      if(word(current,1)== 'Chord'){
        chordz <- str_extract(current, '(?<=\\{)[^\\}]+') 
        chordz <- str_split(chordz, '\\|', simplify = TRUE)
        chordz <- trimws(chordz)
        
        dur <- uniques[which(uniques==current),2]
        oct <- str_extract(chordz[1,], "\\d+")
        
        pit <- c(1:length(chordz))
        for(j in 1:length(chordz)) {
          pit[j] <- word(chordz[1,j], 1)
          if(grepl('sharp',pit[j]) == TRUE){
            pit[j] <- gsub("-sharp", "#", pit[j])
            
          }else if (grepl('flat',pit[j]) == TRUE){
            pit[j] <- gsub("-flat", "-", pit[j])
          }
          
        }#for j-loop 
        
        n1 <- m21$chord$Chord(paste(pit,oct,sep="",collapse = " "))
        n1$quarterLength <- dur
        
        rm(chordz)
      } #belongs to Chord
      
      else{
        ## Creates the Note could run this as its own function, actually might look cleaner
        dur <- uniques[which(uniques==current),2]
        oct <- str_extract(current, "\\d+")
        
        pit <- word(current, 1)
        if(grepl('sharp',pit) == TRUE){
          pit <- gsub("-sharp", "#", pit)
          
        }else if (grepl('flat',pit) == TRUE){
          pit <- gsub("-flat", "-", pit)
        }
        
        n1 <- m21$note$Note(paste0(pit,oct))  #Create the new note
        n1$quarterLength <- dur
        
      }
      
    }else if(word(current,-1) == 'Rest'){
      dur <- uniques[which(uniques==current),2]
      n1 <- m21$note$Rest()
      n1$duration$quarterLength <- dur
    }
    
    ms$append(n1)
    suppressWarnings(rm(list = temps))
    i <- i +1 
  }#belongs to while 
  
  teil <- m21$stream$Part()
  tsPart <- m21$meter$TimeSignature('4/4')
  
  teil$append(tsPart)
  teil$append(ms)
  #teil$insert(k,m21$instrument$Piano())
  teil$insert(k,m21$instrument[[instrumente[k+1]]]())
  
  
  return(teil)
}


CreatePart2 <- function(transition_markov,sl,k){
  i <- 1
  ms <- m21$stream$Measure()
  temps<- c("n1", "dur", "oct", "pit")
  
  while(i <= sl) {
    #print(mitvergangenheit)
    vergangenheit <- mitvergangenheit
    mitvergangenheit  <- current
    print(mitvergangenheit)
    
    past <- paste(vergangenheit ,mitvergangenheit, sep="_")
    print(is.na(transition_markov[past,1])==TRUE)
    
    while(is.na(transition_markov[past,1])==TRUE){
      vergangenheit <- mitvergangenheit
      mitvergangenheit <- sample(uniques$AllThings, 1)
      past <- paste(vergangenheit ,mitvergangenheit, sep="_")
    }
    
    current  <- sample(uniques$AllThings, 1, prob = transition_markov[past,])
    
    if(word(current,-1) == 'Note'|| word(current,1)== 'Chord'){
      
      
      if(word(current,1)== 'Chord'){
        chordz <- str_extract(current, '(?<=\\{)[^\\}]+') 
        chordz <- str_split(chordz, '\\|', simplify = TRUE)
        chordz <- trimws(chordz) # due to split 1 whitespace before n>1 entries
        
        dur <- uniques[which(uniques==current),2]
        oct <- str_extract(chordz[1,], "\\d+")
        
        pit <- c(1:length(chordz))
        for(j in 1:length(chordz)) {
          pit[j] <- word(chordz[1,j], 1)
          if(grepl('sharp',pit[j]) == TRUE){
            pit[j] <- gsub("-sharp", "#", pit[j])
            
          }else if (grepl('flat',pit[j]) == TRUE){
            pit[j] <- gsub("-flat", "-", pit[j])
          }
          
        }#for j-loop 
        
        n1 <- m21$chord$Chord(paste(pit,oct,sep="",collapse = " "))
        n1$quarterLength <- dur
        
        rm(chordz)
      } #belongs to Chord
      
      else{
        ## Creates the Note could run this as its own function, actually might look cleaner
        dur <- uniques[which(uniques==current),2]
        oct <- str_extract(current, "\\d+")
        
        pit <- word(current, 1)
        if(grepl('sharp',pit) == TRUE){
          pit <- gsub("-sharp", "#", pit)
          
        }else if (grepl('flat',pit) == TRUE){
          pit <- gsub("-flat", "-", pit)
        }
        
        n1 <- m21$note$Note(paste0(pit,oct))  #Create the new note
        n1$quarterLength <- dur
        
      }
      
    }else if(word(current,-1) == 'Rest'){
      dur <- uniques[which(uniques==current),2]
      n1 <- m21$note$Rest()
      n1$duration$quarterLength <- dur
    }
    
    ms$append(n1)
    suppressWarnings(rm(list = temps))
    i <- i +1 
  }#belongs to while 
  
  teil <- m21$stream$Part()
  tsPart <- m21$meter$TimeSignature('4/4')
  
  teil$append(tsPart)
  teil$append(ms)
  teil$insert(k,m21$instrument[[instrumente[k+1]]]()) #sets the k-th instrument of the instrument vector in the k-th part
  
  return(teil)
}
```


Now we can either create a score with n=1 or n=2 

```{r n1}  
fasterpiece <- m21$stream$Score(m21$tempo$MetronomeMark(number=120)) #initialize fasterpiece set tempo to chosen one

while (k < length(instrumente)) {
  herz <- py$teilDaten(k,bach) 
  herz %>% mutate(dauer = as.numeric(as.character(dauer))) %>% drop_na() -> herz # Remove Tuplets and Triplets because they are difficult to deal with

  uniques <- data.frame(unique(herz)) # Throws an error but works
  base_matrix <- data.frame(matrix(data = 0, nrow= base::nrow(unique(herz)),ncol= base::nrow(unique(herz))))
  names(base_matrix) <- uniques$AllThings ;rownames(base_matrix) <- uniques$AllThings
  
  
  
  n=1;i=1
  while(i < nrow(herz)- n +1){   #populate base matrix
  
    current = herz[i+n,1]
    past = herz[i,1]
    
    base_matrix[past, current] <- base_matrix[past, current] + 1 
    
    i <- i +1 
  }
  rm(i)
  
  prob_mat <- base_matrix/rowSums(base_matrix)
  prob_mat <- na.omit(prob_mat)
  
  for(o in length(diag(as.matrix(prob_mat[,-1])))){if(diag(as.matrix(prob_mat[,-1]))[o] == TRUE){print("Warning possible absorbing state.")}}
  # There could be an absorbing state but maybe it will not matter.
  
  current <- sample(uniques$AllThings,1)
  sl <- 200 # song length
  
  teil <- CreatePart(prob_mat,sl,k)
  fasterpiece$insert(k, teil)
     
  k <- k+1L
}#belongs to while


fasterpiece$write("midi", fp='/Users/alk/Downloads/fasterpiece_floh.mid')



  






```

```{r n2}
   

fasterpiece2 <- m21$stream$Score(m21$tempo$MetronomeMark(number=120)) # set the tempo to your chosen one

while (k < length(instrumente)) {
  herz <- py$teilDaten(k,bach) 
  herz %>% mutate(dauer = as.numeric(as.character(dauer))) %>% drop_na() -> herz # Remove Tuplets and Triplets because they are difficult to deal with
  uniques <- data.frame(unique(herz))

  #extra step for n=2 basically the same for all n>2
  df2<- expand.grid(a=uniques$AllThings, b=uniques$AllThings) %>% # create all m^n combinations, works the same for n=3 with a,b,c etc
    unite('AllThings',a:b,sep = "_", remove = TRUE)
  
  base_matrix_2 <- data.frame(matrix(data = 0, nrow= base::nrow(df2),ncol= base::nrow(unique(herz))))
  names(base_matrix_2) <- uniques$AllThings ;rownames(base_matrix_2) <- df2$AllThings
  

  
  n=2; i=1
  while(i < nrow(herz)- n +1){ #populate the base matrix
  
    current <- herz[i+n,1]
    mitvergangenheit <- herz[i+n-1,1]
    vergangenheit <- herz[i,1]
    
    
    base_matrix_2[paste(vergangenheit,mitvergangenheit , sep="_"), current] <- base_matrix_2[paste(vergangenheit, mitvergangenheit, sep="_"), current] + 1 
    
    i <- i +1 
  }
  rm(i)
  
  prob_mat_2 <- base_matrix_2/rowSums(base_matrix_2); #new prob mat since some rows are now all 0 there will be naN.
  prob_mat_2 <- na.omit(prob_mat_2) # drop Nan where whole row is 0
  for(o in length(diag(as.matrix(prob_mat_2[,-1])))){if(diag(as.matrix(prob_mat[,-1]))[o] == TRUE){print("Warning possible absorbing state.")}}
  # There could be an absorbing state but maybe it will not matter.
  
  
  current <- sample(uniques$AllThings, 1, prob = prob_mat_2[paste(vergangenheit, mitvergangenheit, sep="_"),]) #starting point
  sl <- 200
  
  teil <-CreatePart2(prob_mat_2,sl,k)
  fasterpiece2$insert(k, teil)
  
  k <- k+1L
}# while k loop


fasterpiece2$write("midi", fp='/Users/alk/Downloads/fasterpiece2_floh.mid')
```







Hier noch ein paar ein Reperaturen zB ein absorbierender Zustand bzw Dinge die nicht gebraucht wurden.

```{r repair ignore}
row.names(prob_mat_mat)[49] <- "Chord {D in octave 3 | D in octave 4 | F in octave 4} Half_Quarter Rest"
prob_mat_mat[49,7] <- 1

if(is.na(transition_markov[paste(mitvergangenheit, vergangenheit , sep="_"),1])==FALSE){current  <- sample(uniques$AllThings, 1,prob =  transition_markov[paste(mitvergangenheit, vergangenheit , sep="_"),])
}else if(is.na(transition_markov[paste(mitvergangenheit, vergangenheit , sep="_"),1])==TRUE){current  <- sample(uniques$AllThings, 1)}
      #if absorbing take flipped sample else if random sample 

if(is.na(transition_markov[paste(mitvergangenheit, vergangenheit , sep="_"),1])==FALSE){current  <- sample(uniques$AllThings, 1,prob =  transition_markov[paste(mitvergangenheit, vergangenheit , sep="_"),])} 

      if(is.na(transition_markov[paste(mitvergangenheit, vergangenheit , sep="_"),1])==TRUE){current  <- sample(uniques$AllThings, 1)}
```


```{r things that aren't needed but incase; For now IGNORE}


#myname <- names(herz)
#herz %>% rename(AllThings = myname) -> herz
#df <- tibble(unique(herz))


#str_extract(tiednote, "\\(([^)]*)\\)") # with (
#str_extract(tiednote, "(?<=\\().*?(?=\\))") #without ()
#eval(parse(text = word(str_extract(tiednote, "(?<=\\().*?(?=\\))"),1))) 

```