def calc_roc_auc(X_test,y_test,dtc,verbose=False):
    """Tests the results of an already-fit classifer. 
    Takes X_test, y_test, classifer, verbose (True" print result)
    Returns the AUC for the roc_curve as a %"""
    y_pred = dtc.predict(X_test)

    FP_rate, TP_rate, thresh = roc_curve(y_test,y_pred)
    roc_auc = auc(FP_rate,TP_rate)
    roc_auc_perc = round(roc_auc*100,3)
    # Your code here 
    if verbose:
        print(f"roc_curve's auc = {roc_auc_perc}%")
    return roc_auc_perc

def tune_params(param_name, param_values):
    """Takes in param_name to tune with param_values, plots train vs test AUC's. 
    Returns df_results and df_style with color coded results"""
    res_list = [[param_name,'train_roc_auc','test_roc_auc']]

    # Loop through all values in param_values
    for value in param_values:
        # Create Model, set params
        dtc_temp = DecisionTreeClassifier(criterion='entropy')
        params={param_name:value}
        dtc_temp.set_params(**params)

        # Fit model
        dtc_temp.fit(X_train, y_train)
        
        # Get roc_auc for training data
        train_roc_auc = calc_roc_auc(X_train,y_train,dtc_temp)
        # Get roc_auc for test data
        test_res_roc_auc = calc_roc_auc(X_test,y_test,dtc_temp)
        # Append value and results to res_list
        res_list.append([value,train_roc_auc,test_res_roc_auc])

    # Turn results into df_results (basically same as using list2df)
    df_results = pd.DataFrame(res_list[1:],columns=res_list[0])
    df_results.set_index(param_name,inplace=True)
    
    # Plot df_results
    df_results.plot()
        
    # Color-coded dataframe s
    import seaborn as sns
    cm = sns.light_palette("green", as_cmap=True)
    df_syle = df_results.style.background_gradient(cmap=cm)#,low=results.min(),high=results.max())

    return df_results, df_syle


# MULTIPLOT
from string import ascii_letters
import numpy as np
import pandas as pd
import seaborn as sns
import matplotlib.pyplot as plt


def multiplot(df):
    """Plots results from df.corr() in a correlation heat map for multicollinearity.
    Returns fig, ax objects"""
    sns.set(style="white")

    # Compute the correlation matrix
    corr = df.corr()

    # Generate a mask for the upper triangle
    mask = np.zeros_like(corr, dtype=np.bool)
    mask[np.triu_indices_from(mask)] = True

    # Set up the matplotlib figure
    f, ax = plt.subplots(figsize=(16, 16))

    # Generate a custom diverging colormap
    cmap = sns.diverging_palette(220, 10, as_cmap=True)

    # Draw the heatmap with the mask and correct aspect ratio
    sns.heatmap(corr, mask=mask, annot=True, cmap=cmap, center=0,
                
    square=True, linewidths=.5, cbar_kws={"shrink": .5})
    return f, ax



# Plots histogram and scatter (vs price) side by side
# Plots histogram and scatter (vs price) side by side
def plot_hist_scat_sns(df, target='index'):
    """Plots seaborne distplots and regplots for columns im datamframe vs target.

    Parameters:
    df (DataFrame): DataFrame.describe() columns will be used. 
    target = name of column containing target variable.assume first coluumn. 
    
    Returns:
    Figures for each column vs target with 2 subplots.
   """
    import matplotlib.ticker as mtick
    import matplotlib.pyplot as plt
    import seaborn as sns
    
    with plt.style.context(('dark_background')):
        ###  DEFINE AESTHETIC CUSTOMIZATIONS  -------------------------------##


#         plt.style.use('dark_background')
        figsize=(9,7)

        # Axis Label fonts
        fontTitle = {'fontsize': 14,
                   'fontweight': 'bold',
                    'fontfamily':'serif'}

        fontAxis = {'fontsize': 12,
                   'fontweight': 'medium',
                    'fontfamily':'serif'}

        fontTicks = {'fontsize': 8,
                   'fontweight':'medium',
                    'fontfamily':'serif'}

        # Formatting dollar sign labels
        fmtPrice = '${x:,.0f}'
        tickPrice = mtick.StrMethodFormatter(fmtPrice)


        ###  PLOTTING ----------------------------- ------------------------ ##

        # Loop through dataframe to plot
        for column in df.describe():
#             print(f'\nCurrent column: {column}')

            # Create figure with subplots for current column
            fig, ax = plt.subplots(figsize=figsize, ncols=2, nrows=2)

            ##  SUBPLOT 1 --------------------------------------------------##
            i,j = 0,0
            ax[i,j].set_title(column.capitalize(),fontdict=fontTitle)

            # Define graphing keyword dictionaries for distplot (Subplot 1)
            hist_kws = {"linewidth": 1, "alpha": 1, "color": 'blue','edgecolor':'w'}
            kde_kws = {"color": "white", "linewidth": 1, "label": "KDE"}

            # Plot distplot on ax[i,j] using hist_kws and kde_kws
            sns.distplot(df[column], norm_hist=True, kde=True,
                         hist_kws = hist_kws, kde_kws = kde_kws,
                         label=column+' histogram', ax=ax[i,j])


            # Set x axis label
            ax[i,j].set_xlabel(column.title(),fontdict=fontAxis)

            # Get x-ticks, rotate labels, and return
            xticklab1 = ax[i,j].get_xticklabels(which = 'both')
            ax[i,j].set_xticklabels(labels=xticklab1, fontdict=fontTicks, rotation=0)
            ax[i,j].xaxis.set_major_formatter(mtick.ScalarFormatter())


            # Set y-label 
            ax[i,j].set_ylabel('Density',fontdict=fontAxis)
            yticklab1=ax[i,j].get_yticklabels(which='both')
            ax[i,j].set_yticklabels(labels=yticklab1,fontdict=fontTicks)
            ax[i,j].yaxis.set_major_formatter(mtick.ScalarFormatter())


            # Set y-grid
            ax[i, j].set_axisbelow(True)
            ax[i, j].grid(axis='y',ls='--')




            ##  SUBPLOT 2-------------------------------------------------- ##
            i,j = 0,1
            ax[i,j].set_title(column.capitalize(),fontdict=fontTitle)

            # Define the kwd dictionaries for scatter and regression line (subplot 2)
            line_kws={"color":"white","alpha":0.5,"lw":4,"ls":":"}
            scatter_kws={'s': 2, 'alpha': 0.5,'marker':'.','color':'blue'}

            # Plot regplot on ax[i,j] using line_kws and scatter_kws
            sns.regplot(df[column], df[target], 
                        line_kws = line_kws,
                        scatter_kws = scatter_kws,
                        ax=ax[i,j])

            # Set x-axis label
            ax[i,j].set_xlabel(column.title(),fontdict=fontAxis)

             # Get x ticks, rotate labels, and return
            xticklab2=ax[i,j].get_xticklabels(which='both')
            ax[i,j].set_xticklabels(labels=xticklab2,fontdict=fontTicks, rotation=0)
            ax[i,j].xaxis.set_major_formatter(mtick.ScalarFormatter())

            # Set  y-axis label
            ax[i,j].set_ylabel(target,fontdict=fontAxis)

            # Get, set, and format y-axis Price labels
            yticklab = ax[i,j].get_yticklabels()
            ax[i,j].set_yticklabels(yticklab,fontdict=fontTicks)
            ax[i,j].yaxis.set_major_formatter(mtick.ScalarFormatter())

    #         ax[i,j].get_yaxis().set_major_formatter(tickPrice) 

            # Set y-grid
            ax[i, j].set_axisbelow(True)
            ax[i, j].grid(axis='y',ls='--')       

            ## ---------- Final layout adjustments ----------- ##
            # Deleted unused subplots 
            fig.delaxes(ax[1,1])
            fig.delaxes(ax[1,0])

            # Optimizing spatial layout
            fig.tight_layout()
            figtitle=column+'_dist_regr_plots.png'
#             plt.savefig(figtitle)
    return 

# Tukey's method using IQR to eliminate 
def detect_outliers(df, n, features):
    """Uses Tukey's method to return outer of interquartile ranges to return indices if outliers in a dataframe.
    Parameters:
    df (DataFrame): DataFrane containing columns of features
    n: default is 0, multiple outlier cutoff  
    
    Returns:
    Index of outliers for .loc
    
    Examples:
    Outliers_to_drop = detect_outliers(data,2,["col1","col2"]) Returning value
    df.loc[Outliers_to_drop] # Show the outliers rows
    data= data.drop(Outliers_to_drop, axis = 0).reset_index(drop=True)
"""

# Drop outliers    

    outlier_indices = []
    # iterate over features(columns)
    for col in features:
        
        # 1st quartile (25%)
        Q1 = np.percentile(df[col], 25)
        # 3rd quartile (75%)
        Q3 = np.percentile(df[col],75)
        
        # Interquartile range (IQR)
        IQR = Q3 - Q1
        # outlier step
        outlier_step = 1.5 * IQR
        
        # Determine a list of indices of outliers for feature col
        outlier_list_col = df[(df[col] < Q1 - outlier_step) | (df[col] > Q3 + outlier_step )].index
        
        # append the found outlier indices for col to the list of outlier indices 
        outlier_indices.extend(outlier_list_col)
        
        # select observations containing more than 2 outliers
        outlier_indices = Counter(outlier_indices)        
        multiple_outliers = list( k for k, v in outlier_indices.items() if v > n )
    return multiple_outliers 


# describe_outliers -- calls detect_outliers
def describe_outliers(df):
    """ Returns a new_df of outliers, and % outliers each col using detect_outliers.
    """
    out_count = 0
    new_df = pd.DataFrame(columns=['total_outliers', 'percent_total'])
    for col in df.columns:
        outies = detect_outliers(df[col])
        out_count += len(outies) 
        new_df.loc[col] = [len(outies), round((len(outies)/len(df.index))*100, 2)]
    new_df.loc['grand_total'] = [sum(new_df['total_outliers']), sum(new_df['percent_total'])]
    return new_df


#### Cohen's d
def Cohen_d(group1, group2):
    '''Compute Cohen's d.
    # group1: Series or NumPy array
    # group2: Series or NumPy array
    # returns a floating point number 
    '''
    diff = group1.mean() - group2.mean()

    n1, n2 = len(group1), len(group2)
    var1 = group1.var()
    var2 = group2.var()

    # Calculate the pooled threshold as shown earlier
    pooled_var = (n1 * var1 + n2 * var2) / (n1 + n2)
    
    # Calculate Cohen's d statistic
    d = diff / np.sqrt(pooled_var)
    
    return d


def plot_pdfs(cohen_d=2):
    """Plot PDFs for distributions that differ by some number of stds.
    
    cohen_d: number of standard deviations between the means
    """
    group1 = scipy.stats.norm(0, 1)
    group2 = scipy.stats.norm(cohen_d, 1)
    xs, ys = evaluate_PDF(group1)
    pyplot.fill_between(xs, ys, label='Group1', color='#ff2289', alpha=0.7)

    xs, ys = evaluate_PDF(group2)
    pyplot.fill_between(xs, ys, label='Group2', color='#376cb0', alpha=0.7)
    
    o, s = overlap_superiority(group1, group2)
    print('overlap', o)
    print('superiority', s)
   
def list2df(list):#, sort_values='index'):
    """ Take in a list where row[0] = column_names and outputs a dataframe.
    
    Keyword arguments:
    set_index -- df.set_index(set_index)
    sortby -- df.sorted()
    """    
    
    df_list = pd.DataFrame(list[1:],columns=list[0])
#     df_list = df_list[1:]

    return df_list

def df_drop_regex(DF, regex_list):
    '''Use a list of regex to remove columns names. Returns new df.
    
    Parameters:
        DF -- input dataframe to remove columns from.
        regex_list -- list of string patterns or regexp to remove.
    
    Returns:
        df_cut -- input df without the dropped columns. 
        '''
    df_cut = DF.copy()
    
    for r in regex_list:
        
        df_cut = df_cut[df_cut.columns.drop(list(df_cut.filter(regex=r)))]
        print(f'Removed {r}\n')
        
    return df_cut



####### MIKE's PLOTTING
# plotting order totals per month in violin plots

def make_violinplot(x,y, title=None, hue=None, ticklabels=None):
  
  '''Plots a violin plot with horizontal mean line, inner stick lines'''
  
  plt.style.use('dark_background')
  fig,ax =plt.subplots(figsize=(12,10))


  sns.violinplot(x, y,cut=2,split=True, scale='count', scale_hue=True,
                 saturation=.5, alpha=.9,bw=.25, palette='Dark2',inner='stick', hue=hue).set_title(title)

  ax.axhline(y.mean(),label='total mean', ls=':', alpha=.5, color='xkcd:yellow')
  ax.set_xticklabels(ticklabels)

  plt.legend()
  plt.show()
  x= df_year_orders['month']
  y= df_year_orders['order_total']
  title = 'Order totals per month with or without discounts'
  hue=df_year_orders['Discount']>0
    
    
### Example usage
# #First, declare variables to be plotted
# x = df_year_orders['month']
# y = df_year_orders['order_total']
# ticks = [v for v in month_dict.values()] 
# title = 'Order totals per month with or without discounts'
# hue = df_year_orders['Discount']>0

### Then call function
# make_violinplot(x,y,title,hue, ticks), 


###########
def plot_wide_kde_thin_bar(series1,sname1, series2, sname2):
    '''Plot series1 and series 2 on wide kde plot with small mean+sem bar plot.'''
    
    ## ADDING add_gridspec usage
    import pandas as pd
    import numpy as np
    from scipy.stats import sem

    import matplotlib.pyplot as plt
    import matplotlib as mpl
    import matplotlib.ticker as ticker

    import seaborn as sns

    from matplotlib import rcParams
    from matplotlib import rc
    rcParams['font.family'] = 'serif'




    # Plot distributions of discounted vs full price groups
    plt.style.use('default')
    # with plt.style.context(('tableau-colorblind10')):
    with plt.style.context(('seaborn-notebook')):

        

        ## ----------- DEFINE AESTHETIC CUSTOMIZATIONS ----------- ##
       # Axis Label fonts
        fontSuptitle ={'fontsize': 22,
                   'fontweight': 'bold',
                    'fontfamily':'serif'}

        fontTitle = {'fontsize': 10,
                   'fontweight': 'medium',
                    'fontfamily':'serif'}

        fontAxis = {'fontsize': 10,
                   'fontweight': 'medium',
                    'fontfamily':'serif'}

        fontTicks = {'fontsize': 8,
                   'fontweight':'medium', 
                    'fontfamily':'serif'}


        ## --------- CREATE FIG BASED ON GRIDSPEC --------- ##
        
        plt.suptitle('Quantity of Units Sold', fontdict = fontSuptitle)

        # Create fig object and declare figsize
        fig = plt.figure(constrained_layout=True, figsize=(8,3))
        
        
        # Define gridspec to create grid coordinates             
        gs = fig.add_gridspec(nrows=1,ncols=10)

        # Assign grid space to ax with add_subplot
        ax0 = fig.add_subplot(gs[0,0:7])
        ax1 = fig.add_subplot(gs[0,7:10])
        
        #Combine into 1 list
        ax = [ax0,ax1]
        
        ### ------------------  SUBPLOT 1  ------------------ ###

        ## --------- Defining series1 and 2 for subplot 1------- ##
        ax[0].set_title('Histogram + KDE',fontdict=fontTitle)

        # Group 1: data, label, hist_kws and kde_kws
        plotS1 = {'data': series1, 'label': sname1.title(),

                   'hist_kws' :
                    {'edgecolor': 'black', 'color':'darkgray','alpha': 0.8, 'lw':0.5},

                   'kde_kws':
                    {'color':'gray', 'linestyle': '--', 'linewidth':2,
                     'label':'kde'}}

        # Group 2: data, label, hist_kws and kde_kws
        plotS2 = {'data': series2,
                    'label': sname2.title(), 

                    'hist_kws' :
                    {'edgecolor': 'black','color':'green','alpha':0.8 ,'lw':0.5},


                    'kde_kws':
                    {'color':'darkgreen','linestyle':':','linewidth':3,'label':'kde'}}
        
        # plot group 1
        sns.distplot(plotS1['data'], label=plotS1['label'],
                   
                     hist_kws = plotS1['hist_kws'], kde_kws = plotS1['kde_kws'],
                     
                     ax=ax[0])   
      

        # plot group 2
        sns.distplot(plotS2['data'], label=plotS2['label'],
                     
                     hist_kws=plotS2['hist_kws'], kde_kws = plotS2['kde_kws'],
                     
                     ax=ax[0])


        ax[0].set_xlabel(series1.name, fontdict=fontAxis)
        ax[0].set_ylabel('Kernel Density Estimation',fontdict=fontAxis)

        ax[0].tick_params(axis='both',labelsize=fontTicks['fontsize'])   
        ax[0].legend()


        ### ------------------  SUBPLOT 2  ------------------ ###
        
        # Import scipy for error bars
        from scipy.stats import sem
    
        # Declare x y group labels(x) and bar heights(y)
        x = [plotS1['label'], plotS2['label']]
        y = [np.mean(plotS1['data']), np.mean(plotS2['data'])]

        yerr = [sem(plotS1['data']), sem(plotS2['data'])]
        err_kws = {'ecolor':'black','capsize':5,'capthick':1,'elinewidth':1}

        # Create the bar plot
        ax[1].bar(x,y,align='center', edgecolor='black', yerr=yerr,error_kw=err_kws,width=0.6)

        
        # Customize subplot 2
        ax[1].set_title('Average Quantities Sold',fontdict=fontTitle)
        ax[1].set_ylabel('Mean +/- SEM ',fontdict=fontAxis)
        ax[1].set_xlabel('')
        
        ax[1].tick_params(axis=y,labelsize=fontTicks['fontsize'])
        ax[1].tick_params(axis=x,labelsize=fontTicks['fontsize']) 

        ax1=ax[1]
        test = ax1.get_xticklabels()
        labels = [x.get_text() for x in test]
        ax1.set_xticklabels([plotS1['label'],plotS2['label']], rotation=45,ha='center')
        
#         xlab = [x.get_text() for x in xlablist]
#         ax[1].set_xticklabels(xlab,rotation=45)
        
#         fig.savefig('H1_EDA_using_gridspec.png')
#         plt.tight_layout()
    #     print(f')
        plt.show()

        return fig,ax
