Only optimize float tensors. (#1069)

candle-core/src/dtype.rs

@@ -67,6 +67,20 @@ impl DType {
             Self::F64 => 8,
         }
     }
+
+    pub fn is_int(&self) -> bool {
+        match self {
+            Self::U8 | Self::U32 | Self::I64 => true,
+            Self::BF16 | Self::F16 | Self::F32 | Self::F64 => false,
+        }
+    }
+
+    pub fn is_float(&self) -> bool {
+        match self {
+            Self::U8 | Self::U32 | Self::I64 => false,
+            Self::BF16 | Self::F16 | Self::F32 | Self::F64 => true,
+        }
+    }
 }
 
 pub trait WithDType:

candle-nn/src/optim.rs

@@ -41,6 +41,10 @@ impl Optimizer for SGD {
     type Config = f64;
 
     fn new(vars: Vec<Var>, learning_rate: f64) -> Result<Self> {
+        let vars = vars
+            .into_iter()
+            .filter(|var| var.dtype().is_float())
+            .collect();
         Ok(Self {
             vars,
             learning_rate,
@@ -116,6 +120,7 @@ impl Optimizer for AdamW {
     fn new(vars: Vec<Var>, params: ParamsAdamW) -> Result<Self> {
         let vars = vars
             .into_iter()
+            .filter(|var| var.dtype().is_float())
             .map(|var| {
                 let dtype = var.dtype();
                 let shape = var.shape();