# CallExpression¶

class hail.expr.CallExpression[source]

Bases: hail.expr.expressions.base_expression.Expression

Expression of type tcall.

>>> call = hl.call(0, 1, phased=False)


Attributes

 dtype The data type of the expression. phased True if the call is phased. ploidy Return the number of alleles of this call.

Methods

 __init__ Initialize self. collect Collect all records of an expression into a local list. describe Print information about type, index, and dependencies. export Export a field to a text file. is_diploid True if the call has ploidy equal to 2. is_haploid True if the call has ploidy equal to 1. is_het Evaluate whether the call includes two different alleles. is_het_non_ref Evaluate whether the call includes two different alleles, neither of which is reference. is_het_ref Evaluate whether the call includes two different alleles, one of which is reference. is_hom_ref Evaluate whether the call includes two reference alleles. is_hom_var Evaluate whether the call includes two identical alternate alleles. is_non_ref Evaluate whether the call includes one or more non-reference alleles. n_alt_alleles Returns the number of non-reference alleles. one_hot_alleles Returns an array containing the summed one-hot encoding of the alleles. show Print the first few rows of the table to the console. summarize Compute and print summary information about the expression. take Collect the first n records of an expression. unphased_diploid_gt_index Return the genotype index for unphased, diploid calls.
__eq__(other)

Returns True if the two expressions are equal.

Examples

>>> x = hl.literal(5)
>>> y = hl.literal(5)
>>> z = hl.literal(1)

>>> hl.eval(x == y)
True

>>> hl.eval(x == z)
False


Notes

This method will fail with an error if the two expressions are not of comparable types.

Parameters: other (Expression) – Expression for equality comparison. BooleanExpression – True if the two expressions are equal.
__ge__(other)

Return self>=value.

__getitem__(item)[source]

Get the i*th* allele.

Examples

Index with a single integer:

>>> hl.eval(call[0])
0

>>> hl.eval(call[1])
1

Parameters: item (int or Expression of type tint32) – Allele index. Expression of type tint32
__gt__(other)

Return self>value.

__le__(other)

Return self<=value.

__lt__(other)

Return self<value.

__ne__(other)

Returns True if the two expressions are not equal.

Examples

>>> x = hl.literal(5)
>>> y = hl.literal(5)
>>> z = hl.literal(1)

>>> hl.eval(x != y)
False

>>> hl.eval(x != z)
True


Notes

This method will fail with an error if the two expressions are not of comparable types.

Parameters: other (Expression) – Expression for inequality comparison. BooleanExpression – True if the two expressions are not equal.
collect(_localize=True)

Collect all records of an expression into a local list.

Examples

Collect all the values from C1:

>>> table1.C1.collect()
[2, 2, 10, 11]


Warning

Extremely experimental.

Warning

The list of records may be very large.

Returns: list
describe(handler=<built-in function print>)

Print information about type, index, and dependencies.

dtype

The data type of the expression.

Returns: HailType
export(path, delimiter='\t', missing='NA', header=True)

Export a field to a text file.

Examples

>>> small_mt.GT.export('output/gt.tsv')
>>> with open('output/gt.tsv', 'r') as f:
...     for line in f:
...         print(line, end='')
locus   alleles 0       1       2       3
1:1     ["A","C"]       0/1     0/1     0/0     0/0
1:2     ["A","C"]       1/1     0/1     1/1     1/1
1:3     ["A","C"]       1/1     0/1     0/1     0/0
1:4     ["A","C"]       1/1     0/1     1/1     1/1

>>> small_mt.GT.export('output/gt-no-header.tsv', header=False)
>>> with open('output/gt-no-header.tsv', 'r') as f:
...     for line in f:
...         print(line, end='')
1:1     ["A","C"]       0/1     0/1     0/0     0/0
1:2     ["A","C"]       1/1     0/1     1/1     1/1
1:3     ["A","C"]       1/1     0/1     0/1     0/0
1:4     ["A","C"]       1/1     0/1     1/1     1/1

>>> small_mt.pop.export('output/pops.tsv')
>>> with open('output/pops.tsv', 'r') as f:
...     for line in f:
...         print(line, end='')
sample_idx      pop
0       2
1       2
2       0
3       2

>>> small_mt.ancestral_af.export('output/ancestral_af.tsv')
>>> with open('output/ancestral_af.tsv', 'r') as f:
...     for line in f:
...         print(line, end='')
locus   alleles ancestral_af
1:1     ["A","C"]       5.3905e-01
1:2     ["A","C"]       8.6768e-01
1:3     ["A","C"]       4.3765e-01
1:4     ["A","C"]       7.6300e-01

>>> mt = small_mt
>>> small_mt.bn.export('output/bn.tsv')
>>> with open('output/bn.tsv', 'r') as f:
...     for line in f:
...         print(line, end='')
bn
{"n_populations":3,"n_samples":4,"n_variants":4,"n_partitions":8,"pop_dist":[1,1,1],"fst":[0.1,0.1,0.1],"mixture":false}


Notes

For entry-indexed expressions, if there is one column key field, the result of calling hl.str() on that field is used as the column header. Otherwise, each compound column key is converted to JSON and used as a column header. For example:

>>> small_mt = small_mt.key_cols_by(s=small_mt.sample_idx, family='fam1')
>>> small_mt.GT.export('output/gt-no-header.tsv')
>>> with open('output/gt-no-header.tsv', 'r') as f:
...     for line in f:
...         print(line, end='')
locus   alleles {"s":0,"family":"fam1"} {"s":1,"family":"fam1"} {"s":2,"family":"fam1"} {"s":3,"family":"fam1"}
1:1     ["A","C"]       0/1     0/1     0/0     0/0
1:2     ["A","C"]       1/1     0/1     1/1     1/1
1:3     ["A","C"]       1/1     0/1     0/1     0/0
1:4     ["A","C"]       1/1     0/1     1/1     1/1

Parameters: path (str) – The path to which to export. delimiter (str) – The string for delimiting columns. missing (str) – The string to output for missing values. header (bool) – When True include a header line.
is_diploid()[source]

True if the call has ploidy equal to 2.

Examples

>>> hl.eval(call.is_diploid())
True

Returns: BooleanExpression
is_haploid()[source]

True if the call has ploidy equal to 1.

Examples

>>> hl.eval(call.is_haploid())
False

Returns: BooleanExpression
is_het()[source]

Evaluate whether the call includes two different alleles.

Examples

>>> hl.eval(call.is_het())
True


Notes

In the diploid biallelic case, a 0/1 call will return True, and 0/0 and 1/1 will return False.

Returns: BooleanExpression – True if the two alleles are different, False if they are the same.
is_het_non_ref()[source]

Evaluate whether the call includes two different alleles, neither of which is reference.

Examples

>>> hl.eval(call.is_het_non_ref())
False


Notes

A biallelic variant may never have a het-non-ref call. Examples of these calls are 1/2 and 2/4.

Returns: BooleanExpression – True if the call includes two different alternate alleles, False otherwise.
is_het_ref()[source]

Evaluate whether the call includes two different alleles, one of which is reference.

Examples

>>> hl.eval(call.is_het_ref())
True

Returns: BooleanExpression – True if the call includes one reference and one alternate allele, False otherwise.
is_hom_ref()[source]

Evaluate whether the call includes two reference alleles.

Examples

>>> hl.eval(call.is_hom_ref())
False

Returns: BooleanExpression – True if the call includes two reference alleles, False otherwise.
is_hom_var()[source]

Evaluate whether the call includes two identical alternate alleles.

Examples

>>> hl.eval(call.is_hom_var())
False

Returns: BooleanExpression – True if the call includes two identical alternate alleles, False otherwise.
is_non_ref()[source]

Evaluate whether the call includes one or more non-reference alleles.

Examples

>>> hl.eval(call.is_non_ref())
True


Notes

In the diploid biallelic case, a 0/0 call will return False, and 0/1 and 1/1 will return True.

Returns: BooleanExpression – True if at least one allele is non-reference, False otherwise.
n_alt_alleles()[source]

Returns the number of non-reference alleles.

Examples

>>> hl.eval(call.n_alt_alleles())
1


Notes

For diploid biallelic calls, this method is equivalent to the alternate allele dosage. For instance, 0/0 will return 0, 0/1 will return 1, and 1/1 will return 2.

Returns: Expression of type tint32 – The number of non-reference alleles.
one_hot_alleles(alleles)[source]

Returns an array containing the summed one-hot encoding of the alleles.

Examples

>>> hl.eval(call.one_hot_alleles(['A', 'T']))
[1, 1]


This one-hot representation is the positional sum of the one-hot encoding for each called allele. For a biallelic variant, the one-hot encoding for a reference allele is [1, 0] and the one-hot encoding for an alternate allele is [0, 1]. Diploid calls would produce the following arrays: [2, 0] for homozygous reference, [1, 1] for heterozygous, and [0, 2] for homozygous alternate.

Parameters: alleles (ArrayStringExpression) – Variant alleles. ArrayInt32Expression – An array of summed one-hot encodings of allele indices.
phased

True if the call is phased.

Examples

>>> hl.eval(call.phased)
False

Returns: BooleanExpression
ploidy

Return the number of alleles of this call.

Examples

>>> hl.eval(call.ploidy)
2


Notes

Currently only ploidy 1 and 2 are supported.

Returns: Expression of type tint32
show(n=None, width=None, truncate=None, types=True, handler=None, n_rows=None, n_cols=None)

Print the first few rows of the table to the console.

Examples

>>> table1.SEX.show()
+-------+-----+
|    ID | SEX |
+-------+-----+
| int32 | str |
+-------+-----+
|     1 | "M" |
|     2 | "M" |
|     3 | "F" |
|     4 | "F" |
+-------+-----+

>>> hl.literal(123).show()
+--------+
| <expr> |
+--------+
|  int32 |
+--------+
|    123 |
+--------+


Warning

Extremely experimental.

Parameters: n (int) – Maximum number of rows to show. width (int) – Horizontal width at which to break columns. truncate (int, optional) – Truncate each field to the given number of characters. If None, truncate fields to the given width. types (bool) – Print an extra header line with the type of each field.
summarize(handler=None)

Compute and print summary information about the expression.

Danger

This functionality is experimental. It may not be tested as well as other parts of Hail and the interface is subject to change.

take(n, _localize=True)

Collect the first n records of an expression.

Examples

Take the first three rows:

>>> table1.X.take(3)
[5, 6, 7]


Warning

Extremely experimental.

Parameters: n (int) – Number of records to take. list
unphased_diploid_gt_index()[source]

Return the genotype index for unphased, diploid calls.

Examples

>>> hl.eval(call.unphased_diploid_gt_index())
1

Returns: Expression of type tint32