Python-DolphinDB Equivalents

This page gives rough equivalents for Python functions. The DolphinDB functions listed below are supported in version 2.00 or above.

The following python libraries are covered:
  1. Python built-in function
  2. NumPy
  3. pandas
  4. SciPy
  5. statsmodels
  6. sklearn
  7. TA-Lib

Python built-in function

Python DolphinDB
== eq
abs abs
all all
any any
bool bool
dict dict
equals eqObj
format strReplace
in in
int int
itertools.product cross + join
join concat
lead / lag move
len strlen / size
pow pow
print print
rjust /zfill lpad /rpad
round round
set set
slice slice
sort isort
str string
type type / typestr
zip loop(pair, x, y)

NumPy

NumPy DolphinDB
numpy.argsort isort/isort!
numpy.averge(weight) wavg
numpy.clip winsorize
numpy.corrcoef corrMatrix
numpy.cov covarMatrix
numpy.cov(fweights) wcovar
numpy.digitize digitize
numpy.max max
numpy.mean mean/avg
numpy.median med
numpy.min min
numpy.percentile / pandas.Series.percentile percentile
numpy.quantile quantileSeries
numpy.quantile / pandas.Series.quantile quantile
numpy.random.beta randBeta
numpy.random.binomial randBinomial
numpy.random.chisquare randChiSquare
numpy.random.exponential randExp
numpy.random.f randF
numpy.random.gamma randGamma
numpy.random.logistic randLogistic
numpy.random.multivariate_normal randMultivariateNormal
numpy.random.normal randNormal
numpy.random.normal norm
numpy.random.poisson randPoisson
numpy.random.rand rand
numpy.random.standard_t randStudent
numpy.random.uniform randUniform
numpy.random.weibull randWeibull
numpy.std stdp
numpy.std(ddof=1) std
numpy.sum sum
numpy.var varp
numpy.var(ddof=1) var

pandas

pandas DolphinDB
df[column] at
pandas.concat concatMatrix
pandas.DataFrame.add / pandas.Series.add withNullFill + add
pandas.DataFrame.append / pandas.Series.append append!
pandas.DataFrame.astype / pandas.Series.astype cast
pandas.DataFrame.bfill / pandas.Series.bfill bfill/bfill!
pandas.DataFrame.corr / pandas.Series.corr corr
pandas.DataFrame.count / pandas.Series.count count
pandas.DataFrame.cummax / pandas.Series.cummax cummax
pandas.DataFrame.cummin / pandas.Series.cummin cummin
pandas.DataFrame.cumprod / pandas.Series.cumprod cumprod
pandas.DataFrame.cumsum / pandas.Series.cumsum cumsum
pandas.DataFrame.describe / pandas.Series.describe summary
pandas.DataFrame.diff / pandas.Series.diff eachPost, deltas
pandas.DataFrame.div / pandas.Series.div withNullFill + div / ratio
pandas.DataFrame.drop / pandas.Series.drop dropColumns!
pandas.DataFrame.dropna / pandas.Series.dropna dropna
pandas.DataFrame.ewm.corr ewmCorr
pandas.DataFrame.ewm.cov ewmCov
pandas.DataFrame.ewm.mean ewmMean
pandas.DataFrame.ewm.var ewmVar
pandas.DataFrame.ffill / pandas.Series.ffill ffill/ffill!
pandas.DataFrame.fillna / pandas.Series.fillna nullFill/nullFill!
pandas.DataFrame.groupby.aggFunc regroup, group by
pandas.DataFrame.head / pandas.Series.head head
pandas.DataFrame.hist / pandas.Series.hist plotHist
pandas.DataFrame.idxmax / pandas.Series.idxmax imax
pandas.DataFrame.idxmin / pandas.Series.idxmin imin
pandas.DataFrame.interpolate / pandas.Series.interpolate interpolate
pandas.DataFrame.interpolate(method='linear') / pandas.Series.interpolate(method='linear') lfill/lfill!
pandas.DataFrame.isin / pandas.Series.isin in
pandas.DataFrame.isnull/pandas.DataFrame.isna isNull
pandas.DataFrame.keys / pandas.Series.keys rowNames / columnNames
pandas.DataFrame.kurt(kurtosis) / pandas.Series.kurt(kurtosis) kurtosis
pandas.DataFrame.mad / pandas.Series.mad mad (useMedian=false)
pandas.DataFrame.mask / pandas.Series.mask mask
pandas.DataFrame.max / pandas.Series.max max
pandas.DataFrame.mean / pandas.Series.mean mean/avg
pandas.DataFrame.median / pandas.Series.median med
pandas.DataFrame.melt unpivot
pandas.DataFrame.merge / pandas.DataFrame.join merge
pandas.DataFrame.min / pandas.Series.min min
pandas.DataFrame.mul / pandas.Series.mul withNullFill + mul
pandas.DataFrame.nlargest(nsmallest) / pandas.Series.nlargest(nsmallest) top + order by / aggrTopN
pandas.DataFrame.notnull/pandas.DataFrame.notna isValid
pandas.DataFrame.nunique / pandas.Series.nunique nunique
pandas.DataFrame.pivot pivot / panel
pandas.DataFrame.prod / pandas.Series.prod prod
pandas.DataFrame.quantile / pandas.Series.quantile quantile
pandas.DataFrame.rename rename!
pandas.DataFrame.rolling / pandas.Series.rolling moving
pandas.DataFrame.sem / pandas.Series.sem sem
pandas.DataFrame.shift / pandas.Series.shift move / tmove / prev / next
pandas.DataFrame.skew / pandas.Series.kurt(skew) skew
pandas.DataFrame.sort_values / pandas.Series.sort_values sort/sort!
pandas.DataFrame.std / pandas.Series.std std
pandas.DataFrame.sub / pandas.Series.sub withNullFill + sub
pandas.DataFrame.sum / pandas.Series.sum sum
pandas.DataFrame.tail / pandas.Series.tail tail
pandas.DataFrame.to_json / pandas.Series.to_json toJson
pandas.DataFrame.transpose transpose
pandas.ewmstd ewmStd
pandas.read_csv loadText / loadTextEx
pandas.read_json fromJson
pandas.rolling_mean mavg
pandas.rolling_median mmed
pandas.rolling_std mstd
pandas.Series.align / pandas.DataFrame.align align
pandas.Series.between between
pandas.Series.copy / pandas.DataFrame.copy copy
pandas.Series.cov covar
pandas.Series.describe / pandas.DataFrame.describe 类似 stat
pandas.Series.duplicated /pandas.DataFrame.duplicated isDuplicated
pandas.Series.iat / pandas.DataFrame.iat cell
pandas.Series.iloc / pandas.DataFrame.iloc cells
pandas.Series.is_monotonic_decreasing isMonotonicIncreasing
pandas.Series.is_monotonic_increasing isMonotonicDecreasing
pandas.Series.loc / pandas.DataFrame.loc loc
pandas.Series.rank / pandas.DataFrame.rank rank
pandas.Series.rank(method='dense') / pandas.DataFrame.rank(method='dense') denseRank
pandas.Series.resample / pandas.DataFrame.resample resample
pandas.Series.str.endswith endsWith
pandas.Series.str.find regexFind
pandas.Series.str.isalnum isAlNum
pandas.Series.str.isalpha isAlpha
pandas.Series.str.isdecimal isDecimal
pandas.Series.str.isdigit isDigit
pandas.Series.str.islower isLower
pandas.Series.str.isnumeric isNumeric
pandas.Series.str.isspace isSpace
pandas.Series.str.istitle isTitle
pandas.Series.str.isupper isUpper
pandas.Series.str.replace strReplace
pandas.Series.str.startswith startsWith
pandas.to_csv saveText
pandas.to_datetime temporalParse
pandas.unique / pandas.DataFrame.unique / pandas.Series.unique distinct

SciPy

SciPy DolphinDB
scipy.interpolate.CubicHermiteSpline cubicHermiteSplineFit
scipy.interpolate.KroghInterpolator kroghInterpolate
scipy.spatial.distance.euclidean euclidean
scipy.stats.beta.cdf(X, a, b) cdfBeta(a, b, X)
scipy.stats.beta.ppf(X, a, b) invBeta
scipy.stats.binom.cdf(X, trials, p) cdfBinomial(trials, p, X)
scipy.stats.binom.ppf(X, trials, p) invBinomial
scipy.stats.boxcox boxcox
scipy.stats.chi2.cdf(x, df) cdfChiSquare(df, X)
scipy.stats.chi2.pdf pdfChiSquare
scipy.stats.chi2.ppf(x, df) invChiSquare
scipy.stats.chisquare chiSquareTest
scipy.stats.expon.cdf(x, scale=mean) cdfExp(mean, X)
scipy.stats.expon.ppf(x, scale=mean) invExp
scipy.stats.f_oneway fTest
scipy.stats.f.cdf(X, dfn, dfd) cdfF(dfn, dfd, X)
scipy.stats.f.pdf pdfF
scipy.stats.f.ppf(X, dfn, dfd) invF
scipy.stats.gamma.cdf(X, shape, scale=scale) cdfGamma(shape, scale, X)
scipy.stats.gamma.ppf(X, shape, scale=scale) invGamma
scipy.stats.ks_2samp ksTest
scipy.stats.kurtosis kurtosis
scipy.stats.logistic.cdf(X, loc=mean,scale=scale) cdfLogistic(mean, scale, X)
scipy.stats.logistic.ppf(X, loc=mean,scale=scale) invLogistic
scipy.stats.mannwhitneyu mannWhitneyUTest
scipy.stats.mstats.winsorize winsorize
scipy.stats.norm.cdf(X, loc=mean, scale=stdev) cdfNormal(mean,stdev,X)
scipy.stats.norm.pdf pdfNormal
scipy.stats.norm.ppf(X, loc=mean, scale=stdev) invNormal
scipy.stats.percentileofscore percentileRank
scipy.stats.poisson.cdf(X, mu=mean) cdfPoisson(mean, X)
scipy.stats.poisson.ppf(X, mu=mean) invPoisson
scipy.stats.sem sem
scipy.stats.shapiro shapiroTest
scipy.stats.skew skew
scipy.stats.spearmanr(X, Y)[0] spearmanr(X, Y)
scipy.stats.t.cdf(X, df) cdfStudent(df, X)
scipy.stats.t.ppf(X, df) invStudent
scipy.stats.ttest_ind tTest
scipy.stats.uniform.cdf(X, loc=lower, scale=upper-lower) cdfUniform(lower, upper, X)
scipy.stats.uniform.ppf(X, loc=lower, scale=upper-lower) invUniform
scipy.stats.weibull_min.cdf(X, alpha, scale=beta) cdfWeibull(alpha, beta, X)
scipy.stats.weibull_min.ppf(X, alpha, scale=beta) invWeibull
scipy.stats.zipfian.cdf(X, exponent, num) cdfZipf(num, exponent, X)
scipy.stats.zscore(ddof=1) zscore

statsmodels

statsmodels DolphinDB
statsmodels.api.stats.anova_lm anova
statsmodels.api.tsa.acf acf
statsmodels.multivariate.manova.MANOVA manova
statsmodels.regression.linear_model.OLS olsolsEx
statsmodels.regression.linear_model.WLS wls
statsmodels.stats.weightstats.ztest zTest
statsmodels.tsa.arima.model.ARIMA arima
statsmodels.tsa.seasonal.STL stl

sklearn

sklearn DolphinDB
sklearn.cluster.k_means kmeans
sklearn.decomposition.PCA pca
sklearn.ensemble.AdaBoostClassifier adaBoostClassifier
sklearn.ensemble.AdaBoostRegressor adaBoostRegressor
sklearn.ensemble.RandomForestClassifier randomForestClassifier
sklearn.ensemble.RandomForestRegressor randomForestRegressor
sklearn.linear_model.ElasticNet elasticNet
sklearn.linear_model.Lasso lasso
sklearn.linear_model.LinearRegression().fit(Y, X).coef_ beta(X, Y)
sklearn.linear_model.LogisticRegression logisticRegression
sklearn.linear_model.Ridge ridge
sklearn.metrics.mutual_info_score mutualInfo
sklearn.mixture.GaussianMixture gmm
sklearn.naive_bayes.GaussianNB gaussianNB
sklearn.naive_bayes.MultinomialNB multinomialNB
sklearn.neighbors.KNeighborsClassifier knn

TA-Lib

TA-Lib DolphinDB
talib.DEMA dema
talib.EMA ema
talib.KAMA kama
talib.LINEARREG_SLOPE / talib.LINEARREG_INTERCEPT linearTimeTrend
talib.MA ma
talib.SMA sma
talib.T3 t3
talib.TEMA tema
talib.TRANGE trueRange
talib.TRIMA trima
talib.WMA wma

The functions listed above are DolphinDB built-in functions. More TA-lib functions are provided in DolphinDB ta module. Refer to DolphinDB tutorial: Technical Analysis Indicator Library for more information.

Note: Contact us via support@dolphindb.com or comment below to send us feedback or report any problems you find.