From a62b58139d17f3dece12a252b0bad0586757106e Mon Sep 17 00:00:00 2001
From: Fredrik Bagge Carlson <baggepinnen@gmail.com>
Date: Wed, 16 Mar 2022 10:08:41 +0100
Subject: [PATCH] add delay margin and frequency to diskmargin printout

---
 docs/src/uncertainty.md | 9 ---------
 src/diskmargin.jl       | 9 ++++++++-
 2 files changed, 8 insertions(+), 10 deletions(-)

diff --git a/docs/src/uncertainty.md b/docs/src/uncertainty.md
index a767c706..7eccf02d 100644
--- a/docs/src/uncertainty.md
+++ b/docs/src/uncertainty.md
@@ -175,20 +175,14 @@ In robust control, we often find ourselves having to consider the feedback inter
         │         │
    y┌───┤         │◄───┐u
     │   └─────────┘    │
-    │                  │
     │      ┌───┐       │
-    │      │   │       │
     └─────►│ K ├───────┘
-           │   │
            └───┘
 ```
 ```
            ┌───┐
-           │   │
     ┌─────►│ Δ ├───────┐
-    │      │   │       │
     │      └───┘       │
-    │                  │
     │   ┌─────────┐    │
   zΔ└───┤         │◄───┘wΔ
         │         │
@@ -196,11 +190,8 @@ In robust control, we often find ourselves having to consider the feedback inter
         │         │
    y┌───┤         │◄───┐u
     │   └─────────┘    │
-    │                  │
     │      ┌───┐       │
-    │      │   │       │
     └─────►│ K ├───────┘
-           │   │
            └───┘
 ```
 
diff --git a/src/diskmargin.jl b/src/diskmargin.jl
index 8e09fb7d..a55336ae 100644
--- a/src/diskmargin.jl
+++ b/src/diskmargin.jl
@@ -57,13 +57,20 @@ Base.propertynames(dm::Diskmargin) = (fieldnames(typeof(dm))..., :margin, :gainm
 function Base.show(io::IO, dm::Diskmargin)
     println(io, "Disk margin with:")
     println(io, "Margin: ", dm.α)
-    println(io, "Frequency: ", dm.ω0)
+    println(io, "Frequency: ", dm.ω0, " rad/s,  ", dm.ω0/(2π), " Hz")
     if dm.γmax < dm.γmin # In this case, we have an "inverted circle"
         println(io, "Gain margins: [$(dm.γmin), Inf]")
     else
         println(io, "Gain margins: [$(dm.γmin), $(dm.γmax)]")
     end
     println(io, "Phase margin: ", dm.ϕm)
+    delaymarg = π/180 * dm.ϕm / dm.ω0
+    print(io, "Delay margin: ", delaymarg, " s")
+    if isdiscrete(dm.L)
+        println(io, ",  ", floor(Int, delaymarg / dm.L.Ts), " samples")
+    else
+        println(io)
+    end
     println(io, "Skew: ", dm.σ)
     println(io, "Worst-case perturbation: ", dm.f0)
 end