feature: support showing a decimal place for CPU usage (#2045)

* feature: support showing a decimal place for CPU usage

* update docs + changelog + schema

* fix basic cpu formatting

CHANGELOG.md

@@ -32,8 +32,9 @@ That said, these are more guidelines rather than hard rules, though the project
 - [#1938](https://github.com/ClementTsang/bottom/pull/1938), [#1980](https://github.com/ClementTsang/bottom/pull/1980): Report average packet size and packet rate.
 - [#2003](https://github.com/ClementTsang/bottom/pull/2003): Configurable default sort column for temperature and disk table widgets.
 - [#1979](https://github.com/ClementTsang/bottom/pull/1979): Add global `bg_color` option to set widget background colour.
-- [#2039](https://github.com/ClementTsang/bottom/pull/2039): Support drawing a line separator between the column headers and data.
+- [#2039](https://github.com/ClementTsang/bottom/pull/2039): Add support for drawing a line separator between the column headers and data.
-- [#1948](https://github.com/ClementTsang/bottom/pull/1948): Support `!=` operator and `!` negation prefixes in query searches.
+- [#1948](https://github.com/ClementTsang/bottom/pull/1948): Add support for both an `!=` operator and `!` negation prefixes in query searches.
+- [#2045](https://github.com/ClementTsang/bottom/pull/2045): Add support for showing a decimal place for CPU usage
 
 ### Changes
 

docs/content/configuration/config-file/cpu.md

@@ -9,3 +9,12 @@ You can configure which CPU graph is shown by default when starting up bottom by
 # One of "all" (default), "average"/"avg"
 default = "average"
 ```
+
+## Show Decimal
+
+You can configure whether CPU usage values are shown with a decimal place by setting `cpu.show_decimal`. Defaults to `false`.
+
+```toml
+[cpu]
+show_decimal = true
+```

sample_configs/default_config.toml

@@ -147,6 +147,9 @@
 # One of "all" (default), "average"/"avg"
 #default = "average"
 
+# Whether to show a decimal place for CPU usage values.
+#show_decimal = false
+
 
 # Disk widget configuration
 #[disk]

schema/nightly/bottom.json

@@ -135,6 +135,13 @@
         "default": {
           "description": "The default selected entry of the CPU widget.",
           "$ref": "#/$defs/CpuDefault"
+        },
+        "show_decimal": {
+          "description": "Whether to show a decimal place for CPU usage values.",
+          "type": [
+            "boolean",
+            "null"
+          ]
         }
       }
     },

src/app.rs

@@ -44,6 +44,7 @@ pub struct AppConfigFields {
     pub use_dot: bool,
     pub cpu_left_legend: bool,
     pub show_average_cpu: bool, // TODO: Unify this in CPU options
+    pub show_cpu_decimal: bool,
     pub use_current_cpu_total: bool,
     pub unnormalized_cpu: bool,
     pub get_process_threads: bool,

src/canvas/widgets/cpu_basic.rs

@@ -47,6 +47,7 @@ impl Painter {
         // TODO: This is pretty ugly. Is there a better way of doing it?
         let mut avg_index = cpu_data.len() + 1;
         let mut avg_row_count = 0;
+        let show_decimal = app_state.app_config_fields.show_cpu_decimal;
         if app_state.app_config_fields.dedicated_average_row
             && app_state.app_config_fields.show_average_cpu
         {
@@ -54,7 +55,7 @@ impl Painter {
                 .iter()
                 .find_position(|&datum| matches!(datum.data_type, CpuDataType::Avg))
             {
-                let (outer, inner, ratio, style) = self.cpu_info(avg);
+                let (outer, inner, ratio, style) = self.cpu_info(avg, show_decimal);
                 let [cores_loc, mut avg_loc] =
                     Layout::vertical([Constraint::Min(0), Constraint::Length(1)]).areas(draw_loc);
 
@@ -93,7 +94,7 @@ impl Painter {
                 if index == avg_index {
                     None
                 } else {
-                    Some(self.cpu_info(cpu))
+                    Some(self.cpu_info(cpu, show_decimal))
                 }
             });
 
@@ -156,7 +157,9 @@ impl Painter {
     }
 
     #[inline]
-    fn cpu_info(&self, data: &CpuData) -> (String, String, f32, tui::style::Style) {
+    fn cpu_info(
+        &self, data: &CpuData, show_decimal: bool,
+    ) -> (String, String, f32, tui::style::Style) {
         let (outer, style) = match data.data_type {
             CpuDataType::Avg => ("AVG".to_string(), self.styles.avg_cpu_colour),
             CpuDataType::Cpu(index) => (
@@ -165,7 +168,11 @@ impl Painter {
             ),
         };
 
-        let inner = format!("{:>3.0}%", data.usage.round());
+        let inner = if show_decimal {
+            format!("{:>5.1}%", data.usage)
+        } else {
+            format!("{:>3.0}%", data.usage.round())
+        };
         let ratio = data.usage / 100.0;
 
         (outer, inner, ratio, style)

src/constants.rs

@@ -395,6 +395,9 @@ pub(crate) const CONFIG_TEXT: &str = r#"# This is a default config file for bott
 # One of "all" (default), "average"/"avg"
 #default = "average"
 
+# Whether to show a decimal place for CPU usage values.
+#show_decimal = false
+
 
 # Disk widget configuration
 #[disk]

src/options.rs

@@ -303,6 +303,7 @@ pub(crate) fn init_app(args: BottomArgs, config: Config) -> Result<(App, BottomL
         temperature_type: get_temperature(args, config)
             .context("Update 'temperature_type' in your config file.")?,
         show_average_cpu: get_show_average_cpu(args, config),
+        show_cpu_decimal: get_show_cpu_decimal(config),
         use_dot: is_flag_enabled!(dot_marker, args.general, config),
         cpu_left_legend: is_flag_enabled!(cpu_left_legend, args.cpu, config),
         use_current_cpu_total: is_flag_enabled!(current_usage, args.process, config),
@@ -768,6 +769,14 @@ fn get_default_cpu_selection(args: &BottomArgs, config: &Config) -> config::cpu:
     }
 }
 
+fn get_show_cpu_decimal(config: &Config) -> bool {
+    config
+        .cpu
+        .as_ref()
+        .and_then(|c| c.show_decimal)
+        .unwrap_or(false)
+}
+
 fn get_table_gap(config: &Config) -> TableGap {
     config
         .flags

src/options/config/cpu.rs

@@ -20,6 +20,9 @@ pub(crate) struct CpuConfig {
     /// The default selected entry of the CPU widget.
     #[serde(default)]
     pub(crate) default: CpuDefault,
+
+    /// Whether to show a decimal place for CPU usage values.
+    pub(crate) show_decimal: Option<bool>,
 }
 
 #[cfg(test)]

src/widgets/cpu_graph.rs

@@ -18,14 +18,14 @@ use crate::{
 
 pub enum CpuWidgetColumn {
     Cpu,
-    Use,
+    Use { show_decimal: bool },
 }
 
 impl ColumnHeader for CpuWidgetColumn {
     fn text(&self) -> Cow<'static, str> {
         match self {
             CpuWidgetColumn::Cpu => "CPU".into(),
-            CpuWidgetColumn::Use => "Use".into(),
+            CpuWidgetColumn::Use { .. } => "Use".into(),
         }
     }
 }
@@ -62,7 +62,7 @@ impl DataToCell<CpuWidgetColumn> for CpuWidgetTableData {
         match &self {
             CpuWidgetTableData::All => match column {
                 CpuWidgetColumn::Cpu => Some("All".into()),
-                CpuWidgetColumn::Use => None,
+                CpuWidgetColumn::Use { .. } => None,
             },
             CpuWidgetTableData::Entry {
                 data_type,
@@ -85,7 +85,11 @@ impl DataToCell<CpuWidgetColumn> for CpuWidgetTableData {
                                 Some(text)
                             }
                         },
-                        CpuWidgetColumn::Use => Some(format!("{:.0}%", last_entry.round()).into()),
+                        CpuWidgetColumn::Use { show_decimal } => Some(if *show_decimal {
+                            format!("{last_entry:.1}%").into()
+                        } else {
+                            format!("{last_entry:.0}%").into()
+                        }),
                     }
                 }
             }
@@ -133,9 +137,14 @@ impl CpuWidgetState {
         config: &AppConfigFields, default_selection: CpuDefault, current_display_time: u64,
         autohide_timer: Option<Instant>, colours: &Styles,
     ) -> Self {
-        const COLUMNS: [Column<CpuWidgetColumn>; 2] = [
+        let columns = [
             Column::soft(CpuWidgetColumn::Cpu, Some(0.5)),
-            Column::soft(CpuWidgetColumn::Use, Some(0.5)),
+            Column::soft(
+                CpuWidgetColumn::Use {
+                    show_decimal: config.show_cpu_decimal,
+                },
+                Some(0.5),
+            ),
         ];
 
         let props = DataTableProps {
@@ -148,7 +157,7 @@ impl CpuWidgetState {
         };
 
         let styling = DataTableStyling::from_palette(colours);
-        let mut table = DataTable::new(COLUMNS, props, styling);
+        let mut table = DataTable::new(columns, props, styling);
         match default_selection {
             CpuDefault::All => {}
             CpuDefault::Average if !config.show_average_cpu => {}