{"id":166954,"date":"2023-04-05T14:32:29","date_gmt":"2023-04-05T14:32:29","guid":{"rendered":"\/knowledge\/forums\/topic\/why-is-the-monitor-value-for-a-define_report_definition_fn-ansys-fluent-udf-zero\/"},"modified":"2023-07-31T12:27:48","modified_gmt":"2023-07-31T12:27:48","slug":"why-is-the-monitor-value-for-a-define_report_definition_fn-ansys-fluent-udf-zero","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/why-is-the-monitor-value-for-a-define_report_definition_fn-ansys-fluent-udf-zero\/","title":{"rendered":"Why is the monitor value for a DEFINE_REPORT_DEFINITION_FN ANSYS Fluent UDF zero?"},"content":{"rendered":"<p>When running Fluent parallel, ensure that you pass the return value to the host process that it can be used for reporting.  If you use Message or Message0 for debugging your UDF (user-defined function), you should get the expected value because most calculations are done on the node processes. But monitoring is done by the Cortex process which gets its data from the host only. If you don&#8217;t pass the data to the host process, you get whatever is stored in memory. It might be zero but it can be any arbitrary number.  You can find more information about message passing with node_to_host_* macros in the ANSYS Fluent Customization Manual, chapter &#8220;Communicating Between the Host and Node Processes&#8221;. For a detailed example that uses REPORT_DEFINITION_FN, refer to solution 2053120: How can an input parameter be used for report expressions in ANSYS Fluent?<\/p>\n","protected":false},"template":"","class_list":["post-166954","topic","type-topic","status-publish","hentry","topic-tag-4391","topic-tag-fluent","topic-tag-fluid-dynamics","topic-tag-general-fluent"],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO 4.9.10 - aioseo.com -->\n\t<meta name=\"description\" content=\"When running Fluent parallel, ensure that you pass the return value to the host process that it can be used for reporting. If you use Message or Message0 for debugging your UDF (user-defined function), you should get the expected value because most calculations are done on the node processes. But monitoring is done by the\" \/>\n\t<meta name=\"robots\" content=\"max-image-preview:large\" \/>\n\t<link rel=\"canonical\" href=\"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/why-is-the-monitor-value-for-a-define_report_definition_fn-ansys-fluent-udf-zero\/\" \/>\n\t<meta name=\"generator\" content=\"All in One SEO (AIOSEO) 4.9.10\" \/>\n\t\t<meta property=\"og:locale\" content=\"en_US\" \/>\n\t\t<meta property=\"og:site_name\" content=\"Ansys Knowledge | Ansys Innovation Space\" \/>\n\t\t<meta property=\"og:type\" content=\"article\" \/>\n\t\t<meta property=\"og:title\" content=\"Why is the monitor value for a DEFINE_REPORT_DEFINITION_FN ANSYS Fluent UDF zero? | Ansys Knowledge\" \/>\n\t\t<meta property=\"og:description\" content=\"When running Fluent parallel, ensure that you pass the return value to the host process that it can be used for reporting. If you use Message or Message0 for debugging your UDF (user-defined function), you should get the expected value because most calculations are done on the node processes. But monitoring is done by the\" \/>\n\t\t<meta property=\"og:url\" content=\"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/why-is-the-monitor-value-for-a-define_report_definition_fn-ansys-fluent-udf-zero\/\" \/>\n\t\t<meta property=\"article:published_time\" content=\"2023-04-05T14:32:29+00:00\" \/>\n\t\t<meta property=\"article:modified_time\" content=\"2023-07-31T12:27:48+00:00\" \/>\n\t\t<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n\t\t<meta name=\"twitter:title\" content=\"Why is the monitor value for a DEFINE_REPORT_DEFINITION_FN ANSYS Fluent UDF zero? | Ansys Knowledge\" \/>\n\t\t<meta name=\"twitter:description\" content=\"When running Fluent parallel, ensure that you pass the return value to the host process that it can be used for reporting. If you use Message or Message0 for debugging your UDF (user-defined function), you should get the expected value because most calculations are done on the node processes. But monitoring is done by the\" \/>\n\t\t<script type=\"application\/ld+json\" class=\"aioseo-schema\">\n\t\t\t{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/knowledge\\\/forums\\\/topic\\\/why-is-the-monitor-value-for-a-define_report_definition_fn-ansys-fluent-udf-zero\\\/#breadcrumblist\",\"itemListElement\":[{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/knowledge#listItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/innovationspace.ansys.com\\\/knowledge\",\"nextItem\":{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/knowledge\\\/topics\\\/#listItem\",\"name\":\"Topics\"}},{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/knowledge\\\/topics\\\/#listItem\",\"position\":2,\"name\":\"Topics\",\"item\":\"https:\\\/\\\/innovationspace.ansys.com\\\/knowledge\\\/topics\\\/\",\"nextItem\":{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/knowledge\\\/forums\\\/topic-tag\\\/fluent\\\/#listItem\",\"name\":\"fluent\"},\"previousItem\":{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/knowledge#listItem\",\"name\":\"Home\"}},{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/knowledge\\\/forums\\\/topic-tag\\\/fluent\\\/#listItem\",\"position\":3,\"name\":\"fluent\",\"item\":\"https:\\\/\\\/innovationspace.ansys.com\\\/knowledge\\\/forums\\\/topic-tag\\\/fluent\\\/\",\"nextItem\":{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/knowledge\\\/forums\\\/topic\\\/why-is-the-monitor-value-for-a-define_report_definition_fn-ansys-fluent-udf-zero\\\/#listItem\",\"name\":\"Why is the monitor value for a DEFINE_REPORT_DEFINITION_FN ANSYS Fluent UDF zero?\"},\"previousItem\":{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/knowledge\\\/topics\\\/#listItem\",\"name\":\"Topics\"}},{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/knowledge\\\/forums\\\/topic\\\/why-is-the-monitor-value-for-a-define_report_definition_fn-ansys-fluent-udf-zero\\\/#listItem\",\"position\":4,\"name\":\"Why is the monitor value for a DEFINE_REPORT_DEFINITION_FN ANSYS Fluent UDF zero?\",\"previousItem\":{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/knowledge\\\/forums\\\/topic-tag\\\/fluent\\\/#listItem\",\"name\":\"fluent\"}}]},{\"@type\":\"Organization\",\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/knowledge\\\/#organization\",\"name\":\"Ansys Knowledge\",\"description\":\"Ansys Innovation Space\",\"url\":\"https:\\\/\\\/innovationspace.ansys.com\\\/knowledge\\\/\"},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/knowledge\\\/forums\\\/topic\\\/why-is-the-monitor-value-for-a-define_report_definition_fn-ansys-fluent-udf-zero\\\/#webpage\",\"url\":\"https:\\\/\\\/innovationspace.ansys.com\\\/knowledge\\\/forums\\\/topic\\\/why-is-the-monitor-value-for-a-define_report_definition_fn-ansys-fluent-udf-zero\\\/\",\"name\":\"Why is the monitor value for a DEFINE_REPORT_DEFINITION_FN ANSYS Fluent UDF zero? | Ansys Knowledge\",\"description\":\"When running Fluent parallel, ensure that you pass the return value to the host process that it can be used for reporting. If you use Message or Message0 for debugging your UDF (user-defined function), you should get the expected value because most calculations are done on the node processes. But monitoring is done by the\",\"inLanguage\":\"en-US\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/knowledge\\\/#website\"},\"breadcrumb\":{\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/knowledge\\\/forums\\\/topic\\\/why-is-the-monitor-value-for-a-define_report_definition_fn-ansys-fluent-udf-zero\\\/#breadcrumblist\"},\"datePublished\":\"2023-04-05T14:32:29+00:00\",\"dateModified\":\"2023-07-31T12:27:48+00:00\"},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/knowledge\\\/#website\",\"url\":\"https:\\\/\\\/innovationspace.ansys.com\\\/knowledge\\\/\",\"name\":\"Ansys Knowledge\",\"description\":\"Ansys Innovation Space\",\"inLanguage\":\"en-US\",\"publisher\":{\"@id\":\"https:\\\/\\\/innovationspace.ansys.com\\\/knowledge\\\/#organization\"}}]}\n\t\t<\/script>\n\t\t<!-- All in One SEO -->\n\n","aioseo_head_json":{"title":"Why is the monitor value for a DEFINE_REPORT_DEFINITION_FN ANSYS Fluent UDF zero? | Ansys Knowledge","description":"When running Fluent parallel, ensure that you pass the return value to the host process that it can be used for reporting. If you use Message or Message0 for debugging your UDF (user-defined function), you should get the expected value because most calculations are done on the node processes. But monitoring is done by the","canonical_url":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/why-is-the-monitor-value-for-a-define_report_definition_fn-ansys-fluent-udf-zero\/","robots":"max-image-preview:large","keywords":"","webmasterTools":{"miscellaneous":""},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"BreadcrumbList","@id":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/why-is-the-monitor-value-for-a-define_report_definition_fn-ansys-fluent-udf-zero\/#breadcrumblist","itemListElement":[{"@type":"ListItem","@id":"https:\/\/innovationspace.ansys.com\/knowledge#listItem","position":1,"name":"Home","item":"https:\/\/innovationspace.ansys.com\/knowledge","nextItem":{"@type":"ListItem","@id":"https:\/\/innovationspace.ansys.com\/knowledge\/topics\/#listItem","name":"Topics"}},{"@type":"ListItem","@id":"https:\/\/innovationspace.ansys.com\/knowledge\/topics\/#listItem","position":2,"name":"Topics","item":"https:\/\/innovationspace.ansys.com\/knowledge\/topics\/","nextItem":{"@type":"ListItem","@id":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic-tag\/fluent\/#listItem","name":"fluent"},"previousItem":{"@type":"ListItem","@id":"https:\/\/innovationspace.ansys.com\/knowledge#listItem","name":"Home"}},{"@type":"ListItem","@id":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic-tag\/fluent\/#listItem","position":3,"name":"fluent","item":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic-tag\/fluent\/","nextItem":{"@type":"ListItem","@id":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/why-is-the-monitor-value-for-a-define_report_definition_fn-ansys-fluent-udf-zero\/#listItem","name":"Why is the monitor value for a DEFINE_REPORT_DEFINITION_FN ANSYS Fluent UDF zero?"},"previousItem":{"@type":"ListItem","@id":"https:\/\/innovationspace.ansys.com\/knowledge\/topics\/#listItem","name":"Topics"}},{"@type":"ListItem","@id":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/why-is-the-monitor-value-for-a-define_report_definition_fn-ansys-fluent-udf-zero\/#listItem","position":4,"name":"Why is the monitor value for a DEFINE_REPORT_DEFINITION_FN ANSYS Fluent UDF zero?","previousItem":{"@type":"ListItem","@id":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic-tag\/fluent\/#listItem","name":"fluent"}}]},{"@type":"Organization","@id":"https:\/\/innovationspace.ansys.com\/knowledge\/#organization","name":"Ansys Knowledge","description":"Ansys Innovation Space","url":"https:\/\/innovationspace.ansys.com\/knowledge\/"},{"@type":"WebPage","@id":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/why-is-the-monitor-value-for-a-define_report_definition_fn-ansys-fluent-udf-zero\/#webpage","url":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/why-is-the-monitor-value-for-a-define_report_definition_fn-ansys-fluent-udf-zero\/","name":"Why is the monitor value for a DEFINE_REPORT_DEFINITION_FN ANSYS Fluent UDF zero? | Ansys Knowledge","description":"When running Fluent parallel, ensure that you pass the return value to the host process that it can be used for reporting. If you use Message or Message0 for debugging your UDF (user-defined function), you should get the expected value because most calculations are done on the node processes. But monitoring is done by the","inLanguage":"en-US","isPartOf":{"@id":"https:\/\/innovationspace.ansys.com\/knowledge\/#website"},"breadcrumb":{"@id":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/why-is-the-monitor-value-for-a-define_report_definition_fn-ansys-fluent-udf-zero\/#breadcrumblist"},"datePublished":"2023-04-05T14:32:29+00:00","dateModified":"2023-07-31T12:27:48+00:00"},{"@type":"WebSite","@id":"https:\/\/innovationspace.ansys.com\/knowledge\/#website","url":"https:\/\/innovationspace.ansys.com\/knowledge\/","name":"Ansys Knowledge","description":"Ansys Innovation Space","inLanguage":"en-US","publisher":{"@id":"https:\/\/innovationspace.ansys.com\/knowledge\/#organization"}}]},"og:locale":"en_US","og:site_name":"Ansys Knowledge | Ansys Innovation Space","og:type":"article","og:title":"Why is the monitor value for a DEFINE_REPORT_DEFINITION_FN ANSYS Fluent UDF zero? | Ansys Knowledge","og:description":"When running Fluent parallel, ensure that you pass the return value to the host process that it can be used for reporting. If you use Message or Message0 for debugging your UDF (user-defined function), you should get the expected value because most calculations are done on the node processes. But monitoring is done by the","og:url":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/why-is-the-monitor-value-for-a-define_report_definition_fn-ansys-fluent-udf-zero\/","article:published_time":"2023-04-05T14:32:29+00:00","article:modified_time":"2023-07-31T12:27:48+00:00","twitter:card":"summary_large_image","twitter:title":"Why is the monitor value for a DEFINE_REPORT_DEFINITION_FN ANSYS Fluent UDF zero? | Ansys Knowledge","twitter:description":"When running Fluent parallel, ensure that you pass the return value to the host process that it can be used for reporting. If you use Message or Message0 for debugging your UDF (user-defined function), you should get the expected value because most calculations are done on the node processes. But monitoring is done by the"},"aioseo_meta_data":{"post_id":"166954","title":null,"description":null,"keywords":null,"keyphrases":null,"primary_term":null,"canonical_url":null,"og_title":null,"og_description":null,"og_object_type":"default","og_image_type":"default","og_image_url":null,"og_image_width":null,"og_image_height":null,"og_image_custom_url":null,"og_image_custom_fields":null,"og_video":null,"og_custom_url":null,"og_article_section":null,"og_article_tags":null,"twitter_use_og":false,"twitter_card":"default","twitter_image_type":"default","twitter_image_url":null,"twitter_image_custom_url":null,"twitter_image_custom_fields":null,"twitter_title":null,"twitter_description":null,"schema":{"blockGraphs":[],"customGraphs":[],"default":{"data":{"Article":[],"Course":[],"Dataset":[],"FAQPage":[],"Movie":[],"Person":[],"Product":[],"ProductReview":[],"Car":[],"Recipe":[],"Service":[],"SoftwareApplication":[],"WebPage":[]},"graphName":"","isEnabled":true},"graphs":[]},"schema_type":"default","schema_type_options":null,"pillar_content":false,"robots_default":true,"robots_noindex":false,"robots_noarchive":false,"robots_nosnippet":false,"robots_nofollow":false,"robots_noimageindex":false,"robots_noodp":false,"robots_notranslate":false,"robots_max_snippet":null,"robots_max_videopreview":null,"robots_max_imagepreview":"large","priority":null,"frequency":null,"local_seo":null,"limit_modified_date":false,"created":"2025-10-17 23:25:26","updated":"2026-07-29 20:43:58","ai":null,"breadcrumb_settings":null,"seo_analyzer_scan_date":null},"aioseo_breadcrumb":"<div class=\"aioseo-breadcrumbs\"><span class=\"aioseo-breadcrumb\">\n\t\t\t<a href=\"https:\/\/innovationspace.ansys.com\/knowledge\" title=\"Home\">Home<\/a>\n\t\t<\/span><span class=\"aioseo-breadcrumb-separator\">&raquo;<\/span><span class=\"aioseo-breadcrumb\">\n\t\t\t<a href=\"https:\/\/innovationspace.ansys.com\/knowledge\/topics\/\" title=\"Topics\">Topics<\/a>\n\t\t<\/span><span class=\"aioseo-breadcrumb-separator\">&raquo;<\/span><span class=\"aioseo-breadcrumb\">\n\t\t\t<a href=\"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic-tag\/fluent\/\" title=\"fluent\">fluent<\/a>\n\t\t<\/span><span class=\"aioseo-breadcrumb-separator\">&raquo;<\/span><span class=\"aioseo-breadcrumb\">\n\t\t\tWhy is the monitor value for a DEFINE_REPORT_DEFINITION_FN ANSYS Fluent UDF zero?\n\t\t<\/span><\/div>","aioseo_breadcrumb_json":[{"label":"Home","link":"https:\/\/innovationspace.ansys.com\/knowledge"},{"label":"Topics","link":"https:\/\/innovationspace.ansys.com\/knowledge\/topics\/"},{"label":"fluent","link":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic-tag\/fluent\/"},{"label":"Why is the monitor value for a DEFINE_REPORT_DEFINITION_FN ANSYS Fluent UDF zero?","link":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/why-is-the-monitor-value-for-a-define_report_definition_fn-ansys-fluent-udf-zero\/"}],"acf":[],"custom_fields":[{"0":{"_wp_page_template":["default"],"_bbp_last_active_time":["5\/4\/2023 20:20"],"_bbp_forum_id":["27796"],"_bbp_author_ip":["209.182.204.162"],"_btv_view_count":["1029"],"siebel_km_number":["2053790"],"product_version":["19"],"km_published_date":["2018-03-28T00:00:00.000Z"],"family":["Fluid Dynamics"],"application_name":["FLUENT"]},"test":"articlesansys-com"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/knowledge\/wp-json\/wp\/v2\/topics\/166954","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/innovationspace.ansys.com\/knowledge\/wp-json\/wp\/v2\/topics"}],"about":[{"href":"https:\/\/innovationspace.ansys.com\/knowledge\/wp-json\/wp\/v2\/types\/topic"}],"version-history":[{"count":0,"href":"https:\/\/innovationspace.ansys.com\/knowledge\/wp-json\/wp\/v2\/topics\/166954\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/knowledge\/wp-json\/wp\/v2\/media?parent=166954"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}