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STDLIB
Reference Manual
Version 1.18.1

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Table of Contents

STDLIB (App)
array
- Top of manual page
- default/1
- fix/1
- foldl/3
- foldr/3
- from_list/1
- from_list/2
- from_orddict/1
- from_orddict/2
- get/2
- is_array/1
- is_fix/1
- map/2
- new/0
- new/1
- new/2
- relax/1
- reset/2
- resize/1
- resize/2
- set/3
- size/1
- sparse_foldl/3
- sparse_foldr/3
- sparse_map/2
- sparse_size/1
- sparse_to_list/1
- sparse_to_orddict/1
- to_list/1
- to_orddict/1
base64
- Top of manual page
- encode/1
- encode_to_string/1
- decode/1
- decode_to_string/1
- mime_decode/1
- mime_decode_to_string/1
beam_lib
- Top of manual page
- chunks/2
- chunks/3
- version/1
- md5/1
- info/1
- cmp/2
- cmp_dirs/2
- diff_dirs/2
- strip/1
- strip_files/1
- strip_release/1
- format_error/1
- crypto_key_fun/1
- clear_crypto_key_fun/0
binary
- Top of manual page
- at/2
- bin_to_list/1
- bin_to_list/2
- bin_to_list/3
- compile_pattern/1
- copy/1
- copy/2
- decode_unsigned/1
- decode_unsigned/2
- encode_unsigned/1
- encode_unsigned/2
- first/1
- last/1
- list_to_bin/1
- longest_common_prefix/1
- longest_common_suffix/1
- match/2
- match/3
- matches/2
- matches/3
- part/2
- part/3
- referenced_byte_size/1
- replace/3
- replace/4
- split/2
- split/3
c
- Top of manual page
- bt/1
- c/1
- c/2
- cd/1
- flush/0
- help/0
- i/0
- ni/0
- i/3
- l/1
- lc/1
- ls/0
- ls/1
- m/0
- m/1
- memory/0
- memory/1
- nc/1
- nc/2
- nl/1
- pid/3
- pwd/0
- q/0
- regs/0
- nregs/0
- xm/1
- y/1
- y/2
calendar
- Top of manual page
- date_to_gregorian_days/1
- date_to_gregorian_days/3
- datetime_to_gregorian_seconds/1
- day_of_the_week/1
- day_of_the_week/3
- gregorian_days_to_date/1
- gregorian_seconds_to_datetime/1
- is_leap_year/1
- iso_week_number/0
- iso_week_number/1
- last_day_of_the_month/2
- local_time/0
- local_time_to_universal_time/1
- local_time_to_universal_time_dst/1
- now_to_local_time/1
- now_to_universal_time/1
- now_to_datetime/1
- seconds_to_daystime/1
- seconds_to_time/1
- time_difference/2
- time_to_seconds/1
- universal_time/0
- universal_time_to_local_time/1
- valid_date/1
- valid_date/3
dets
- Top of manual page
- all/0
- bchunk/2
- close/1
- delete/2
- delete_all_objects/1
- delete_object/2
- first/1
- foldl/3
- foldr/3
- from_ets/2
- info/1
- info/2
- init_table/2
- init_table/3
- insert/2
- insert_new/2
- is_compatible_bchunk_format/2
- is_dets_file/1
- lookup/2
- match/1
- match/2
- match/3
- match_delete/2
- match_object/1
- match_object/2
- match_object/3
- member/2
- next/2
- open_file/1
- open_file/2
- pid2name/1
- repair_continuation/2
- safe_fixtable/2
- select/1
- select/2
- select/3
- select_delete/2
- slot/2
- sync/1
- table/1
- table/2
- to_ets/2
- traverse/2
- update_counter/3
dict
- Top of manual page
- append/3
- append_list/3
- erase/2
- fetch/2
- fetch_keys/1
- filter/2
- find/2
- fold/3
- from_list/1
- is_key/2
- map/2
- merge/3
- new/0
- size/1
- store/3
- to_list/1
- update/3
- update/4
- update_counter/3
digraph
- Top of manual page
- add_edge/3
- add_edge/4
- add_edge/5
- add_vertex/1
- add_vertex/2
- add_vertex/3
- del_edge/2
- del_edges/2
- del_path/3
- del_vertex/2
- del_vertices/2
- delete/1
- edge/2
- edges/1
- edges/2
- get_cycle/2
- get_path/3
- get_short_cycle/2
- get_short_path/3
- in_degree/2
- in_edges/2
- in_neighbours/2
- info/1
- new/0
- new/1
- no_edges/1
- no_vertices/1
- out_degree/2
- out_edges/2
- out_neighbours/2
- vertex/2
- vertices/1
digraph_utils
- Top of manual page
- arborescence_root/1
- components/1
- condensation/1
- cyclic_strong_components/1
- is_acyclic/1
- is_arborescence/1
- is_tree/1
- loop_vertices/1
- postorder/1
- preorder/1
- reachable/2
- reachable_neighbours/2
- reaching/2
- reaching_neighbours/2
- strong_components/1
- subgraph/2
- subgraph/3
- topsort/1
epp
- Top of manual page
- open/2
- open/3
- close/1
- parse_erl_form/1
- parse_file/3
- format_error/1
erl_eval
- Top of manual page
- exprs/2
- exprs/3
- exprs/4
- expr/2
- expr/3
- expr/4
- expr/5
- expr_list/2
- expr_list/3
- expr_list/4
- new_bindings/0
- bindings/1
- binding/2
- add_binding/3
- del_binding/2
erl_expand_records
- Top of manual page
- module/2
erl_id_trans
- Top of manual page
- parse_transform/2
erl_internal
- Top of manual page
- bif/2
- guard_bif/2
- type_test/2
- arith_op/2
- bool_op/2
- comp_op/2
- list_op/2
- send_op/2
- op_type/2
erl_lint
- Top of manual page
- module/1
- module/2
- module/3
- is_guard_test/1
- format_error/1
erl_parse
- Top of manual page
- parse_form/1
- parse_exprs/1
- parse_term/1
- format_error/1
- tokens/1
- tokens/2
- normalise/1
- abstract/1
erl_pp
- Top of manual page
- form/1
- form/2
- attribute/1
- attribute/2
- function/1
- function/2
- guard/1
- guard/2
- exprs/1
- exprs/2
- exprs/3
- expr/1
- expr/2
- expr/3
- expr/4
erl_scan
- Top of manual page
- string/1
- string/2
- string/3
- tokens/3
- tokens/4
- reserved_word/1
- token_info/1
- token_info/2
- attributes_info/1
- attributes_info/2
- set_attribute/3
- format_error/1
erl_tar
- Top of manual page
- add/3
- add/4
- close/1
- create/2
- create/3
- extract/1
- extract/2
- format_error/1
- open/2
- table/1
- table/2
- t/1
- tt/1
ets
- Top of manual page
- all/0
- delete/1
- delete/2
- delete_all_objects/1
- delete_object/2
- file2tab/1
- file2tab/2
- first/1
- foldl/3
- foldr/3
- from_dets/2
- fun2ms/1
- give_away/3
- i/0
- i/1
- info/1
- info/2
- init_table/2
- insert/2
- insert_new/2
- is_compiled_ms/1
- last/1
- lookup/2
- lookup_element/3
- match/2
- match/3
- match/1
- match_delete/2
- match_object/2
- match_object/3
- match_object/1
- match_spec_compile/1
- match_spec_run/2
- member/2
- new/2
- next/2
- prev/2
- rename/2
- repair_continuation/2
- safe_fixtable/2
- select/2
- select/3
- select/1
- select_count/2
- select_delete/2
- select_reverse/2
- select_reverse/3
- select_reverse/1
- setopts/2
- slot/2
- tab2file/2
- tab2file/3
- tab2list/1
- tabfile_info/1
- table/1
- table/2
- test_ms/2
- to_dets/2
- update_counter/3
- update_counter/3
- update_counter/3
- update_element/3
- update_element/3
file_sorter
- Top of manual page
- sort/1
- sort/2
- sort/3
- keysort/2
- keysort/3
- keysort/4
- merge/2
- merge/3
- keymerge/3
- keymerge/4
- check/1
- check/2
- keycheck/2
- keycheck/3
filelib
- Top of manual page
- ensure_dir/1
- file_size/1
- fold_files/5
- is_dir/1
- is_file/1
- is_regular/1
- last_modified/1
- wildcard/1
- wildcard/2
filename
- Top of manual page
- absname/1
- absname/2
- absname_join/2
- basename/1
- basename/2
- dirname/1
- extension/1
- flatten/1
- join/1
- join/2
- nativename/1
- pathtype/1
- rootname/1
- rootname/2
- split/1
- find_src/1
- find_src/2
gb_sets
- Top of manual page
- add/2
- add_element/2
- balance/1
- delete/2
- delete_any/2
- del_element/2
- difference/2
- subtract/2
- empty/0
- new/0
- filter/2
- fold/3
- from_list/1
- from_ordset/1
- insert/2
- intersection/2
- intersection/1
- is_disjoint/2
- is_empty/1
- is_member/2
- is_element/2
- is_set/1
- is_subset/2
- iterator/1
- largest/1
- next/1
- singleton/1
- size/1
- smallest/1
- take_largest/1
- take_smallest/1
- to_list/1
- union/2
- union/1
gb_trees
- Top of manual page
- balance/1
- delete/2
- delete_any/2
- empty/0
- enter/3
- from_orddict/1
- get/2
- insert/3
- is_defined/2
- is_empty/1
- iterator/1
- keys/1
- largest/1
- lookup/2
- map/2
- next/1
- size/1
- smallest/1
- take_largest/1
- take_smallest/1
- to_list/1
- update/3
- values/1
gen_event
- Top of manual page
- start_link/0
- start_link/1
- start/0
- start/1
- add_handler/3
- add_sup_handler/3
- notify/2
- sync_notify/2
- call/3
- call/4
- delete_handler/3
- swap_handler/3
- swap_sup_handler/3
- which_handlers/1
- stop/1
- Module:init/1
- Module:handle_event/2
- Module:handle_call/2
- Module:handle_info/2
- Module:terminate/2
- Module:code_change/3
- Module:format_status/2
gen_fsm
- Top of manual page
- start_link/3
- start_link/4
- start/3
- start/4
- send_event/2
- send_all_state_event/2
- sync_send_event/2
- sync_send_event/3
- sync_send_all_state_event/2
- sync_send_all_state_event/3
- reply/2
- send_event_after/2
- start_timer/2
- cancel_timer/1
- enter_loop/4
- enter_loop/5
- enter_loop/5
- enter_loop/6
- Module:init/1
- Module:StateName/2
- Module:handle_event/3
- Module:StateName/3
- Module:handle_sync_event/4
- Module:handle_info/3
- Module:terminate/3
- Module:code_change/4
- Module:format_status/2
gen_server
- Top of manual page
- start_link/3
- start_link/4
- start/3
- start/4
- call/2
- call/3
- multi_call/2
- multi_call/3
- multi_call/4
- cast/2
- abcast/2
- abcast/3
- reply/2
- enter_loop/3
- enter_loop/4
- enter_loop/4
- enter_loop/5
- Module:init/1
- Module:handle_call/3
- Module:handle_cast/2
- Module:handle_info/2
- Module:terminate/2
- Module:code_change/3
- Module:format_status/2
io
- Top of manual page
- columns/0
- columns/1
- put_chars/1
- put_chars/2
- nl/0
- nl/1
- get_chars/2
- get_chars/3
- get_line/1
- get_line/2
- getopts/0
- getopts/1
- setopts/1
- setopts/2
- write/1
- write/2
- read/1
- read/2
- read/3
- fwrite/1
- fwrite/2
- fwrite/3
- format/1
- format/2
- format/3
- fread/2
- fread/3
- rows/0
- rows/1
- scan_erl_exprs/1
- scan_erl_exprs/2
- scan_erl_exprs/3
- scan_erl_form/1
- scan_erl_form/2
- scan_erl_form/3
- parse_erl_exprs/1
- parse_erl_exprs/2
- parse_erl_exprs/3
- parse_erl_form/1
- parse_erl_form/2
- parse_erl_form/3
io_lib
- Top of manual page
- nl/0
- write/1
- write/2
- print/1
- print/4
- fwrite/2
- format/2
- fread/2
- fread/3
- write_atom/1
- write_string/1
- write_char/1
- indentation/2
- char_list/1
- deep_char_list/1
- printable_list/1
lib
- Top of manual page
- flush_receive/0
- error_message/2
- progname/0
- nonl/1
- send/2
- sendw/2
lists
- Top of manual page
- all/2
- any/2
- append/1
- append/2
- concat/1
- delete/2
- dropwhile/2
- duplicate/2
- filter/2
- flatlength/1
- flatmap/2
- flatten/1
- flatten/2
- foldl/3
- foldr/3
- foreach/2
- keydelete/3
- keyfind/3
- keymap/3
- keymember/3
- keymerge/3
- keyreplace/4
- keysearch/3
- keysort/2
- keystore/4
- keytake/3
- last/1
- map/2
- mapfoldl/3
- mapfoldr/3
- max/1
- member/2
- merge/1
- merge/2
- merge/3
- merge3/3
- min/1
- nth/2
- nthtail/2
- partition/2
- prefix/2
- reverse/1
- reverse/2
- seq/2
- seq/3
- sort/1
- sort/2
- split/2
- splitwith/2
- sublist/2
- sublist/3
- subtract/2
- suffix/2
- sum/1
- takewhile/2
- ukeymerge/3
- ukeysort/2
- umerge/1
- umerge/2
- umerge/3
- umerge3/3
- unzip/1
- unzip3/1
- usort/1
- usort/2
- zip/2
- zip3/3
- zipwith/3
- zipwith3/4
log_mf_h
- Top of manual page
- init/3
- init/4
math
- Top of manual page
- pi/0
- sin/1
- cos/1
- tan/1
- asin/1
- acos/1
- atan/1
- atan2/2
- sinh/1
- cosh/1
- tanh/1
- asinh/1
- acosh/1
- atanh/1
- exp/1
- log/1
- log10/1
- pow/2
- sqrt/1
- erf/1
- erfc/1
ms_transform
- Top of manual page
- parse_transform/2
- transform_from_shell/3
- format_error/1
orddict
- Top of manual page
- append/3
- append_list/3
- erase/2
- fetch/2
- fetch_keys/1
- filter/2
- find/2
- fold/3
- from_list/1
- is_key/2
- map/2
- merge/3
- new/0
- size/1
- store/3
- to_list/1
- update/3
- update/4
- update_counter/3
ordsets
- Top of manual page
- new/0
- is_set/1
- size/1
- to_list/1
- from_list/1
- is_element/2
- add_element/2
- del_element/2
- union/2
- union/1
- intersection/2
- intersection/1
- is_disjoint/2
- subtract/2
- is_subset/2
- fold/3
- filter/2
pg
- Top of manual page
- create/1
- create/2
- join/2
- send/2
- esend/2
- members/1
pool
- Top of manual page
- start/1
- start/2
- attach/1
- stop/0
- get_nodes/0
- pspawn/3
- pspawn_link/3
- get_node/0
proc_lib
- Top of manual page
- spawn/1
- spawn/2
- spawn/3
- spawn/4
- spawn_link/1
- spawn_link/2
- spawn_link/3
- spawn_link/4
- spawn_opt/2
- spawn_opt/3
- spawn_opt/4
- spawn_opt/5
- start/3
- start/4
- start/5
- start_link/3
- start_link/4
- start_link/5
- init_ack/1
- init_ack/2
- format/1
- initial_call/1
- translate_initial_call/1
- hibernate/3
proplists
- Top of manual page
- append_values/2
- compact/1
- delete/2
- expand/2
- get_all_values/2
- get_bool/2
- get_keys/1
- get_value/2
- get_value/3
- is_defined/2
- lookup/2
- lookup_all/2
- normalize/2
- property/1
- property/2
- split/2
- substitute_aliases/2
- substitute_negations/2
- unfold/1
qlc
- Top of manual page
- append/1
- append/2
- cursor/1
- cursor/2
- delete_cursor/1
- eval/1
- eval/2
- e/1
- e/2
- fold/3
- fold/4
- format_error/1
- info/1
- info/2
- keysort/2
- keysort/3
- next_answers/1
- next_answers/2
- q/1
- q/2
- sort/1
- sort/2
- string_to_handle/1
- string_to_handle/2
- string_to_handle/3
- table/2
queue
- Top of manual page
- new/0
- is_queue/1
- is_empty/1
- len/1
- in/2
- in_r/2
- out/1
- out_r/1
- from_list/1
- to_list/1
- reverse/1
- split/2
- join/2
- filter/2
- member/2
- get/1
- get_r/1
- drop/1
- drop_r/1
- peek/1
- peek_r/1
- cons/2
- head/1
- tail/1
- snoc/2
- daeh/1
- last/1
- liat/1
- init/1
- lait/1
random
- Top of manual page
- seed/0
- seed/3
- seed/1
- seed0/0
- uniform/0
- uniform/1
- uniform_s/1
- uniform_s/2
re
- Top of manual page
- compile/1
- compile/2
- run/2
- run/3
- replace/3
- replace/4
- split/2
- split/3
sets
- Top of manual page
- new/0
- is_set/1
- size/1
- to_list/1
- from_list/1
- is_element/2
- add_element/2
- del_element/2
- union/2
- union/1
- intersection/2
- intersection/1
- is_disjoint/2
- subtract/2
- is_subset/2
- fold/3
- filter/2
shell
- Top of manual page
- history/1
- results/1
- catch_exception/1
- prompt_func/1
- start_restricted/1
- stop_restricted/0
shell_default
slave
- Top of manual page
- start/1
- start/2
- start/3
- start_link/1
- start_link/2
- start_link/3
- stop/1
- pseudo/1
- pseudo/2
- relay/1
sofs
- Top of manual page
- a_function/1
- a_function/2
- canonical_relation/1
- composite/2
- constant_function/2
- converse/1
- difference/2
- digraph_to_family/1
- digraph_to_family/2
- domain/1
- drestriction/2
- drestriction/3
- empty_set/0
- extension/3
- family/1
- family/2
- family_difference/2
- family_domain/1
- family_field/1
- family_intersection/1
- family_intersection/2
- family_projection/2
- family_range/1
- family_specification/2
- family_to_digraph/1
- family_to_digraph/2
- family_to_relation/1
- family_union/1
- family_union/2
- field/1
- from_external/2
- from_sets/1
- from_term/1
- from_term/2
- image/2
- intersection/1
- intersection/2
- intersection_of_family/1
- inverse/1
- inverse_image/2
- is_a_function/1
- is_disjoint/2
- is_empty_set/1
- is_equal/2
- is_set/1
- is_sofs_set/1
- is_subset/2
- is_type/1
- join/4
- multiple_relative_product/2
- no_elements/1
- partition/1
- partition/2
- partition/3
- partition_family/2
- product/1
- product/2
- projection/2
- range/1
- relation/1
- relation/2
- relation_to_family/1
- relative_product/1
- relative_product/2
- relative_product1/2
- restriction/2
- restriction/3
- set/1
- set/2
- specification/2
- strict_relation/1
- substitution/2
- symdiff/2
- symmetric_partition/2
- to_external/1
- to_sets/1
- type/1
- union/1
- union/2
- union_of_family/1
- weak_relation/1
string
- Top of manual page
- len/1
- equal/2
- concat/2
- chr/2
- rchr/2
- str/2
- rstr/2
- span/2
- cspan/2
- substr/2
- substr/3
- tokens/2
- join/2
- chars/2
- chars/3
- copies/2
- words/1
- words/2
- sub_word/2
- sub_word/3
- strip/1
- strip/2
- strip/3
- left/2
- left/3
- right/2
- right/3
- centre/2
- centre/3
- sub_string/2
- sub_string/3
- to_float/1
- to_integer/1
- to_lower/1
- to_upper/1
supervisor
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- start_link/2
- start_link/3
- start_child/2
- terminate_child/2
- delete_child/2
- restart_child/2
- which_children/1
- count_children/1
- check_childspecs/1
- Module:init/1
supervisor_bridge
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- start_link/2
- start_link/3
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sys
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- log/2
- log/3
- log_to_file/2
- log_to_file/3
- statistics/2
- statistics/3
- trace/2
- trace/3
- no_debug/1
- no_debug/2
- suspend/1
- suspend/2
- resume/1
- resume/2
- change_code/4
- change_code/5
- get_status/1
- get_status/2
- install/2
- install/3
- remove/2
- remove/3
- debug_options/1
- get_debug/3
- handle_debug/4
- handle_system_msg/6
- print_log/1
- Mod:system_continue/3
- Mod:system_terminate/4
- Mod:system_code_change/4
timer
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- start/0
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- send_after/2
- send_after/3
- kill_after/1
- kill_after/2
- exit_after/2
- exit_after/3
- apply_interval/4
- send_interval/2
- send_interval/3
- cancel/1
- sleep/1
- tc/1
- tc/2
- tc/3
- now_diff/2
- seconds/1
- minutes/1
- hours/1
- hms/3
unicode
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- characters_to_list/2
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- encoding_to_bom/1
win32reg
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- change_key_create/2
- close/1
- current_key/1
- delete_key/1
- delete_value/2
- expand/1
- format_error/1
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- set_value/3
- sub_keys/1
- value/2
- values/1
zip
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- zip/2
- zip/3
- create/2
- create/3
- unzip/1
- unzip/2
- extract/1
- extract/2
- foldl/3
- list_dir/1
- list_dir/2
- table/1
- table/2
- t/1
- tt/1
- zip_open/1
- zip_open/2
- zip_list_dir/1
- zip_get/1
- zip_get/2
- zip_close/1

math

MODULE

math

MODULE SUMMARY

Mathematical Functions

DESCRIPTION

This module provides an interface to a number of mathematical functions.

Note

Not all functions are implemented on all platforms. In particular, the erf/1 and erfc/1 functions are not implemented on Windows.

EXPORTS

pi() -> float()

A useful number.

sin(X)
cos(X)
tan(X)
asin(X)
acos(X)
atan(X)
atan2(Y, X)
sinh(X)
cosh(X)
tanh(X)
asinh(X)
acosh(X)
atanh(X)
exp(X)
log(X)
log10(X)
pow(X, Y)
sqrt(X)

Types:

X = Y = number()

A collection of math functions which return floats. Arguments are numbers.

erf(X) -> float()

Types:

X = number()

Returns the error function of X, where

erf(X) = 2/sqrt(pi)*integral from 0 to X of exp(-t*t) dt.

erfc(X) -> float()

Types:

X = number()

erfc(X) returns 1.0 - erf(X), computed by methods that avoid cancellation for large X.

Bugs

As these are the C library, the bugs are the same.