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## Class NumericColumnSummary<T>

• Type Parameters:
`T` - the numeric type e.g. Integer, Double
All Implemented Interfaces:
Serializable

```@PublicEvolving
public class NumericColumnSummary<T>
extends ColumnSummary
implements Serializable```
Generic Column Summary for Numeric Types.

Some values are considered "missing" where "missing" is defined as null, NaN, or Infinity. These values are ignored in some calculations like mean, variance, and standardDeviation.

Uses the Kahan summation algorithm to avoid numeric instability when computing variance. The algorithm is described in: "Scalable and Numerically Stable Descriptive Statistics in SystemML", Tian et al, International Conference on Data Engineering 2012.

Serialized Form
• ### Constructor Summary

Constructors
Constructor and Description
```NumericColumnSummary(long nonMissingCount, long nullCount, long nanCount, long infinityCount, T min, T max, T sum, Double mean, Double variance, Double standardDeviation)```
• ### Method Summary

All Methods
Modifier and Type Method and Description
`long` `getInfinityCount()`
Number of values that are positive or negative infinity.
`T` `getMax()`
`Double` `getMean()`
Null, NaN, and Infinite values are ignored in this calculation.
`T` `getMin()`
`long` `getMissingCount()`
The number of "missing" values where "missing" is defined as null, NaN, or Infinity.
`long` `getNanCount()`
Number of values that are NaN.
`long` `getNonMissingCount()`
The number of values that are not null, NaN, or Infinity.
`long` `getNonNullCount()`
The number of non-null values in this column.
`long` `getNullCount()`
The number of null values in this column.
`Double` `getStandardDeviation()`
Standard Deviation is a measure of variation in a set of numbers.
`T` `getSum()`
`Double` `getVariance()`
Variance is a measure of how far a set of numbers are spread out.
`String` `toString()`
• ### Methods inherited from class org.apache.flink.api.java.summarize.ColumnSummary

`containsNonNull, containsNull, getTotalCount`
• ### Methods inherited from class java.lang.Object

`clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait`
• ### Constructor Detail

• #### NumericColumnSummary

```public NumericColumnSummary(long nonMissingCount,
long nullCount,
long nanCount,
long infinityCount,
T min,
T max,
T sum,
Double mean,
Double variance,
Double standardDeviation)```
• ### Method Detail

• #### getMissingCount

`public long getMissingCount()`
The number of "missing" values where "missing" is defined as null, NaN, or Infinity.

These values are ignored in some calculations like mean, variance, and standardDeviation.

• #### getNonMissingCount

`public long getNonMissingCount()`
The number of values that are not null, NaN, or Infinity.
• #### getNonNullCount

`public long getNonNullCount()`
The number of non-null values in this column.
Specified by:
`getNonNullCount` in class `ColumnSummary`
• #### getNullCount

`public long getNullCount()`
Description copied from class: `ColumnSummary`
The number of null values in this column.
Specified by:
`getNullCount` in class `ColumnSummary`
• #### getNanCount

`public long getNanCount()`
Number of values that are NaN.

(always zero for types like Short, Integer, Long)

• #### getInfinityCount

`public long getInfinityCount()`
Number of values that are positive or negative infinity.

(always zero for types like Short, Integer, Long)

• #### getMin

`public T getMin()`
• #### getMax

`public T getMax()`
• #### getSum

`public T getSum()`
• #### getMean

`public Double getMean()`
Null, NaN, and Infinite values are ignored in this calculation.
Arithmetic Mean
• #### getVariance

`public Double getVariance()`
Variance is a measure of how far a set of numbers are spread out.

Null, NaN, and Infinite values are ignored in this calculation.

Variance
• #### getStandardDeviation

`public Double getStandardDeviation()`
Standard Deviation is a measure of variation in a set of numbers. It is the square root of the variance.

Null, NaN, and Infinite values are ignored in this calculation.

`public String toString()`
`toString` in class `Object`